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Influence de la qualité du bois sur les dimensions des copeaux produits par une équarrisseuse-fragmenteuseCaceres Cuadros, Claudia 23 April 2018 (has links)
La présente étude a eu pour objectif principal d’évaluer l’effet de la qualité du bois d’épinette noire et du pin gris sur les dimensions des copeaux papetiers produits par une équarrisseuse-fragmenteuse. Afin de couvrir certains aspects de l’aménagement forestier de ces espèces, le travail s’est orienté vers l’étude des relations entre la provenance des billes, la position des billes dans la tige et la pratique de l’éclaircie commerciale vis-à-vis la qualité du bois et son comportement à la fragmentation. Ainsi, des attributs de masse volumique et de croissance des cernes, le nombre et la taille des nœuds, la masse volumique basale et certaines propriétés mécaniques ont été déterminés pour les parties de la tige soumises à la fragmentation. Dans un premier volet, des billes d’épinette noire provenant de deux sites écartés par un gradient latitudinal d’environ 300 km (47°N, 50°N) furent fragmentées. Celles provenant du site avec un taux de croissance plus faible (50°N) et qui présentaient une masse volumique et des propriétés mécaniques plus élevées ont produit les copeaux plus minces. Un deuxième volet a évalué l’effet de la position de la bille dans la tige sur la fragmentation de cette même espèce. L’augmentation du nombre et de la taille des nœuds suivant la hauteur dans la tige était la cause principale de la production des copeaux plus épais. Cependant, des copeaux plus épais furent aussi produits en bas de la tige, ce qui fut attribué à son défilement plus prononcé. Un troisième volet a été consacré à étudier l’effet de l’éclaircie et de la position de la bille dans la tige pour le pin gris. Les billes provenant des parcelles éclaircies ont produit des copeaux plus minces que ceux obtenus avec des billes provenant d’une parcelle naturelle. Toutefois, la faible taille de l’échantillon dans ce cas invite à la prudence. Le pin gris produirait des copeaux plus épais que l'épinette noire lorsque produits sous les mêmes conditions de coupe. La variation de l’épaisseur des copeaux avec la position de la bille dans la tige serait semblable à celle de l’épinette noire. D’autre part, l’augmentation de la largeur de coupe a produit dans tous les cas des copeaux plus épais. La taille des nœuds serait un paramètre critique agissant sur les dimensions des copeaux. De plus, la variation de la masse volumique des cernes et de la croissance des cernes et les propriétés de flexion statique sembleraient avoir un rôle important sur le mécanisme de formation des copeaux. Les dimensions des copeaux pourraient ainsi être mieux ajustées selon les exigences des papetières si les scieries avaient plus de contrôle et de connaissances sur les attributs spécifiques de leur matière première. / The main goal of this research was to evaluate the effect of wood quality on the dimensions of black spruce and jack pine chips produced with a chipper-canter for pulping purposes. Some aspects of the forest management of these species were studied, namely: the log provenance, the position of the log in the stem, and the commercial thinning, in order to evaluate wood quality and its response to fragmentation. Thus, the growth ring characteristics, the number and size of knots, the basic density, and various mechanical properties potentially involved in chip formation were assessed on the external parts of the log which were subjected to fragmentation. Firstly, black spruce logs coming from two sites separated by 300 km of latitudinal gradient (47°N, 50°N) were fragmented. For a given cutting width, a log coming from a slow growth rate site (50°N) with high ring density attributes and a corresponding high basic density and mechanical properties provided thinner chips. Secondly, the effect of the log position within the stem in the fragmentation process was evaluated for the same species. The increase of the size and number of knots up the stem was the main cause of producing thicker chips towards the top of the stem. However, the production of thicker chips at the bottom logs was attributed to their pronounced taper. Finally, the effects of the commercial thinning and the log position in the stem were evaluated on jack pine. Jack pine logs coming from thinned stands seem to produce chips of smaller dimensions compared to logs from a natural stand. However, these results should be interpreted with caution due to the small sample size used. Under the same cutting conditions, jack pine had a higher mean chip thickness compared to black spruce. Chip thickness variation with the log position in the stem was similar between the two species. Moreover, the increase in cutting width produced thicker chips in all cases. The size of knots appeared to be critical in chip dimension. In addition, the variation in wood density attributes, growth rings characteristics, and bending properties would appear to have a considerable role in the chip formation mechanism. Ultimately, chip dimensions could be adjusted to pulp mills standards if sawmills will have more control and knowledge of their wood raw material specific attributes.
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Modélisation de la distribution précoloniale du pin blanc en Moyenne-Mauricie à partir des carnets d'arpentageMauri Ortuno, Eduard 17 April 2018 (has links)
Cette étude avait pour objectif de fournir un outil pour guider la restauration écologique du pin blanc en Moyenne-Mauricie (Québec, Canada), une espèce largement récoltée pendant le 19e siècle. Les hypothèses sont (1) l'existence d'une relation entre la présence/absence du pin blanc au 19e siècle décrite par les carnets d'arpentage et certaines variables environnementales, et (2) l'existence de différences significatives entre les prévalences (3) et entre les abondances relatives du 19e siècle et présentes. Les résultats montrent que la présence de pin blanc était plus probable sur les dépôts d'épandage et alluviaux, les dépôts glaciaires minces et rocheux, les expositions S-SW-W et les positions topographiques en sommet et haut de pente, au 19e siècle. La prévalence des individus matures dans la région est passée de 0,282 à 0,161, et leur abondance relative dans les peuplements contenant du pin blanc, de 46,5% à 11,8%. Le pin blanc serait donc, aujourd'hui, 6,9 fois moins abondant.
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Caractérisation des composés organiques volatils issus du séchage du bois. Application au chêne rouge et au pin grisVoinot, Damien 13 April 2018 (has links)
Cette étude porte sur la caractérisation et la quantification des composés organiques volatils (COV) issus du séchage par déshumidification du chêne rouge et du séchage conventionnel à moyenne température du pin gris. Les méthodes retenues pour l’étude sont NCASI IM/CAN/WP-99.02, NCASI MD-99 et US-EPA 25A. Nous avons également employé une nouvelle technique de caractérisation des molécules volatiles: la Headspace-SPME, permettant la simulation du séchage du bois de pin et de chêne au laboratoire. Le pin gris a présenté des taux d’émission de COV très élevés: 2,24 gCOV/kgbois sec. Les principaux monoterpènes identifiés parmi les volatils issus du séchage du pin gris sont: alpha-pinène, beta-pinène et 3-carène. Les principaux composés polaires captés pour le pin gris sont: méthanol, acétaldéhyde et méthyle acétate, et pour le chêne rouge: acide acétique (ultra-majoritaire), méthanol et éthanol. La Headspace-SPME a permis l’identification de plusieurs polyphénols volatils provenant du chêne rouge (eugénol, etc.) et de sesquiterpènes bioactifs comme l’alpha-humulène, le caryophyllène dans le cas du pin gris. / This study focuses on the characterization and quantification of the volatile organic compounds (VOC) emitted during the dehumidification drying of red oak and the conventional drying of Jack pine at medium temperature. The methods used in this study were NCASI IM/CAN/WP-99.02, NCASI MD-99 and US-EPA 25A. We also employed a new technique for characterizing the volatile molecules: Headspace-SPME, which enables the laboratory simulation of pine and oak drying. Jack pine showed very high VOC emission rates: 2,24 gVOC/kgODW. The main monoterpenes identified among the volatiles released during the drying of jack pine were: alpha-pinene, beta-pinene and 3-carene. The main polar compounds collected from jack pine were methanol, acetaldehyde and methyl acetate, and the main polar compounds collected from red oak were acetic acid (vastly predominant), methanol and ethanol. Headspace-SPME enabled the identification of several volatile polyphenols (eugenol, etc.) released by red oak, as well as the identification of bioactive sesquiterpenes (such as alpha-humulene and caryophyllene) released by Jack pine.
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Vergleich der Stabilität von Schanzschrauben im Knochen im externen Fixateurverbund zu ausgewählten Zeitpunkten am SchafmodellReuther, Theresa Maria 21 June 2006 (has links)
Externe Fixateure werden häufig für die Stabilisierung und Behandlung schwerer Frakturen genutzt. Schraubenkanalinfektionen können dabei zu Komplikationen, wie Osteomyelitis und Stabilitätsverlusten führen. Es ist unklar, ob Schraubenkanalinfektionen zu Schraubenlockerungen führen, oder aber ob der Stabilitätsverlust von Schrauben in Schraubenkanalinfektionen resultiert. Das Ziel dieser Studie ist es, einen Zusammenhang zwischen der mechanischen Stabilität, dem Auftreten von Infektionen und der osseären Verankerung darzustellen. An 27 Schafen wurde eine standardisierte Osteotomie (3mm weiter Frakturspalt) der rechten Tibia durchgeführt und mit einem monolateralem Fixateur externe stabilisiert. Während der täglichen Pinpflege wurde die Haut um die Schraubeneintrittsstellen begutachtet. Radiologische Verlaufskontrollen erfolgten in wöchentlichen Abständen. Nach 3, 6 und 9 Wochen wurden die Tiere getötet, die Ausdrehmomente der Schrauben gemessen und mikrobiologische Abstriche genommen. Knochenschnitte durch die Schraubenkanäle wurden für histologische, histochemische und histomorphometrische Analysen genommen. In dieser Studie scheint es zu einer Zunahme der Stabilisierung der osseären Verankerung während des Heilungsverlaufes zu kommen. Da die kortikale Knochendichte über die Zeit abnimmt, kann die zunehmend stabilere Verankerung der Schrauben einzig über eine gleichzeitige periostale Kallusdichtezunahme erklärt werden. Die größten Ausdrehmomente des neugebildeten periostalen Kallus wurden zum Sechswochenzeitpunkt gemessen. Danach nimmt die periostale Kallusfläche ab, wohingegen die Kallusdichte zunimmt. Die mikrobiologische Besiedelungsrate (15%) war dreifach höher als die klinisch bestätigten Infektionen. Hingegen war die Osteolyserate (28%) doppelt so hoch wie die mikrobiologisch bestätigte Infektionsrate. Eine Korrelation zwischen Infektion, Osteolyse und Pinlockerung konnte nicht gefunden werden. / External fixators are frequently used for the stabilization and the treatment of problematic fractures. Pin track infections have been shown to cause complications such as osteomyelitis and loss of stability of osteosynthesis. It remains unclear, whether pin track infection provokes pin loosening, or loss of the pin stability results in pin track infections. The aim of this study was to investigate the correlation between the mechanical stability of pins, the incidence of pin track infections and the osseus anchorage of pins. 27 sheep underwent a standardized osteotomy (3 mm gap) of the right tibia. The tibiae were stabilized by a monolateral external fixator. Within the daily pin care routine, the skin around the pin entries was scored. Radiographs were taken at weekly intervals. After 3, 6 and 9 weeks, the animals were sacrificed, the extraction torque of all pins was determined and microbiological analyses were taken. Bone sections through the pintracks were taken for histological, histochemical and histomorphometrical analysis. This study reveals an increasing stability of osseous pinanchorage over the course of healing. As the cortical bone density decreased over time, the increased anchorage-stability of the pins can only be explained by the simultaneous increase of the periosteal callus bone density. The magnitude of the extraction force is determined by the newbuilt periosteal callus, which is at its biggest value at six weeks. Afterwards, the periosteal callus area abates, while the callus bone density accumulates. The microbiologically affirmed infection rate (15%) was three times higher than the one clinical ascertained. In contrast the evidence of osteolysis (28%) was twice as high as the microbiologically diagnosed infection-rate. Despite the low infection rate, evidence of cortical lysis coud not be prevented. No correlation could be found between infection, osteolysis and pin loosening.
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Notation financière et comportement des acteurs sur le marché financier / Credit rating and behavior of agents in financial marketDammak, Neila 29 January 2013 (has links)
L'objectif de cette thèse est d'analyser le rôle des agences de notation sur le marché financier. Notre contribution consiste à mieux comprendre l'influence des annonces de notation sur les acteurs du marché français des actions (investisseurs et analystes financiers).La première question porte sur l'apport informatif délivré par les agences de notation et l'impact de leurs décisions. Afin de répondre à cette question, nous avons conduit une étude d'évènement à l'annonce de notation en distinguant les annonces par nature, type et catégorie.Cette recherche permet de prouver que les annonces de notation ont globalement un impact sur le marché des actions. L'impact dépend de la nature de l'annonce, des informations fournies dans les rapports de notation, des changements de note entre catégories et de ceux effectués dans la catégorie spéculative. Enfin, le niveau de la note dépend des caractéristiques financières et comptables de l'entreprise notée.La seconde question porte sur le rôle bénéfique des agences de notation sur les marchés. Afin de répondre à cette deuxième question, nous avons conduit une recherche qui consiste à analyser l'évolution de l'asymétrie d'information entre les investisseurs et de la liquidité autour des annonces de notation.Cette recherche prouve que les annonces positives (respectivement négatives) entraînent une diminution (respectivement augmentation) de l'asymétrie d'information sur le marché des actions. Les résultats prouvent également que les annonces positives et neutres, à l'inverse des annonces négatives, entraînent une réduction des fourchettes de prix et une amélioration des volumes de transactions. Ces deux effets concomitants traduisent une amélioration (respectivement détérioration) de la liquidité du marché lors des annonces positives et neutres (respectivement négatives).La troisième question porte sur l'utilité des annonces de notation pour les analystes lors de leurs prévisions. Afin de répondre à cette question, nous avons mené une recherche qui consiste à étudier l'évolution de la dispersion et de l'erreur des prévisions des analystes autour des annonces de notation.Les résultats mettent en évidence une relation inverse entre les caractéristiques des prévisions des analystes financiers et la nature de l'annonce de notation. Les annonces positives et neutres réduisent l'erreur et la dispersion des prévisions d'analystes.Ce travail de recherche permet d'attester de la réelle importance du contenu informationnel des annonces de notation pour le marché des actions et de la réelle contribution des annonces à l'amélioration de la communication financière sur le marché. / The main objective of this thesis is to analyze the role of rating agencies on the financial market. Our contribution consists in a better understanding of the impact of rating announcements on the agents on the French financial market (both investors and analysts).First we focus on the information content of announcements by rating agencies and the impact of theirs decisions in the market. To answer this question, we made an event study at the rating announcements, by identifying them by nature, type and category.This research highlights the fact that the rating announcements generally have an impact on the stock market. This impact depends on the nature of the announcement, the information provided in the reports as well as score changes between categories and within the speculative category. Moreover, the rating level depends on the firm financial and accounting characteristics.Second, we intend to understand the beneficial role of rating agencies on the financial markets. To answer this question, we analyzed the evolution of the information asymmetry and stock market liquidity around rating announcements.Our results show that positive announcements (respectively negative) lead to a decrease (respectively increase) of information asymmetry. We also found that positive and neutral announcements, unlike the negative ones, lead to a reduction of bid-ask spread and to an increase of transactions volumes. Both effects reflect higher (respectively lower) stock market liquidity when the announcements are positive or neutral (respectively negative).Finally, we focus on the study of the impact of rating announcements on analysts' forecasts. For this purpose, we studied the evolution of the analysts' forecasts dispersion and errors around rating announcements.Our results indicate an inverse relationship between the characteristics of financial analysts' forecasts and the nature of the rating announcement. Indeed, positive and neutral announcements reduce the error and the dispersion of analysts' forecasts.This research shows the informative content of rating announcements on the stock market and the real contribution of the announcements by improving financial communication.
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Utveckling av ett verktyg för lossning och montering av masterpinne i larvkedjaHelme, Lisa, Halatchev, Linnea January 2019 (has links)
Detta är ett examensarbete på 15 högskolepoäng inom Teknisk design vid Luleå Tekniska Universitet. Arbetet har genomförts på uppdrag av Nevo Maskin AB som är en företag som utför reparationer och service av entreprenadmaskiner. Detta produktutvecklingsprojekt har genomförts i samarbete med Sigma Industry East North. Syftet med detta projekt är att förbättra och förenkla arbetet med en Trackpress. Arbetet ska göras säkrare, mobilt och mer ergonomiskt för användaren. En Trackpress används för att demontera och byta masterpinne i länken på larvkedjan på en grävmaskin. Detta arbete behandlar mellansegmentet (12-45 ton) av grävmaskiner. Verktyget som används på Nevo Maskin består av tre huvudsakliga delar: en bygel som läggs ovanpå bandet, en cylinder som expanderar med hjälp av tryckluft och en kompressor som styr tryckluften. Kompletterande delar måste användas mellan länken och cylindern för att den ska nå att pressa ut masterpinnen på länken. Verktyget väger 86 kg och kan inte hanteras av en person, utan ett lyfthjälpmedel måste användas. Ibland lyfts verktyget av två personer, men detta är ytterst oergonomiskt och medför stora risker för arbetsskador. För att förbättra detta verktyg har vi arbetat efter en designprocess där faser med förstudie, litteraturstudie, idéarbete och detaljutveckling genomförts för att utveckla ett koncept. I designprocessen som används i det här projektet är en av faserna idéarbete, där vi använt oss av workshops där medlemmarna skissar, diskuterar och skriver ned idéer som kommer fram. Genom att använda oss av olika metoder och olika grupper av människor i våra workshops kunde vi få flera infallsvinklar på problemet. Vidare har vi inom de olika faserna genomfört studiebesök, användarstudier, intervjuer, marknadsundersökning och kreativa metoder för att arbeta fram ett koncept som ritades upp i NX och Inventor. Resultatet är ett utvecklat verktyg kallat Masterpusher som består av tre delar. En ram uppbyggd av två parallella plåtar, med en platta baktill där cylindern placeras mellan de två sidoplåtarna, en domkraft för positionering av hydraulcylindern i höjdled och en insats för centrering av verktyget. I botten på ramen finns två skenor för att cylindern och domkraften inte inte ska falla ned. Ett kompletterande koncept för förflyttning och transport har rekommenderats för vidareutveckling. Konceptet medger säkrare hantering och mer ergonomiskt arbetssätt. Vikten har reducerats och materialåtgången minskats. Förbättringen innebär även en minskad produktionskostnad vilket bidrar till en konkurrensfördel jämfört med de konkurrenter som finns idag. Nyckelord: Industridesign, Teknisk design, Konstruktion, Master pin pusher, Produktutveckling, Ergonomi, Nevo Maskin AB / This is a bachelor degree project in Industrial design engineering at Luleå University of Technology. It has been carried out at the request of Nevo Maskin AB, a company that performs service and repairs on heavy construction equipment. The project has been executed in collaboration with Sigma Industry East North in Luleå. The purpose of this project is to improve and simplify the work with a Trackpress. The work process must be made safe, mobile and ergonomic for the user. The Trackpress is a tool that is used for dismantling and replacing the master pin in the link of the caterpillar chain on excavators. The project covers the middle segment of excavators which means excavators between 12 to 45 tons and this is the most common segment of excavators repaired by Nevo Maskin AB. The Trackpress tool used by Nevo Maskin AB consists of three parts: a frame that is placed over the caterpillar chain, a hydraulic cylinder that expands by compressed air and a compressor that controls the compressed air. Supplementary parts are needed between the link and cylinder in order for it to reach the master pin, here they use whatever they have in reach. The exciting Trackpress weighs 86 kgs and cannot be lifted by one sole person, a lifting device must be used. Sometimes two people lifts it but this is not to recommend because of the great risk of injuries. To improve the Trackpress the project has been carried out through a design process with five phases of planning, feasibility study, literature study, ideation and detail development to develop a concept. in one of the phases, Ideation, we have worked with workshops where the members draw, discuss, and write down all the ideas generated. By using different methods and groups of people in the workshops we got different angles and points of view on the problem. Furthermore we have done field trips, user studies, interviews market research and creative methods to develop a concept that was drawn in NX and Inventor. The final concept consists of three parts, a frame constructed by two parallel steel plates with another plate in the rear, a jack for positioning the cylinder, which is placed on top of the jack and between the parallel plates and a additional part for centering the tool over the chain. In the bottom there are two rails that keep the jack in place. A concept for transporting the tool has been left for future development. The concept idea gives the user safer handling of the tool and a more ergonomic way of working with it. The weight and the material consumtion has been reduced. This improvement also reduces de production cost whitch gives the company an advantage against other competitors in the same segment. Keywords: Industrial design engineering, Master pin pusher, Construction, Product development, Ergonomics, Nevo Maskin AB
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On-line C-arm intrinsic calibration by means of an accurate method of line detection using the radon transform / On-line C-arm Calibration intrinsèque "On-line" d'un C-arm par une méthode de détection de droite avec la transformée de RadonSpencer, Benjamin 18 December 2015 (has links)
Les ``C-arm'' sont des systémes de radiologie interventionnelle fréquemment utilisés en salle d'opération ou au lit du patient. Des images 3D des structures anatomiques internes peuvent être calculées à partir de multiples radiographies acquises sur un ``C-arm mobile'' et isocentrique décrivant une trajectoire généralement circulaire autour du patient. Pour cela, la géométrie conique d'acquisition de chaque radiographie doit être précisément connue. Malheureusement, les C-arm se déforment en général au cours de la trajectoire. De plus leur motorisation engendre des oscillations non reproductibles. Ils doivent donc être calibrés au cours de l'acquisition. Ma thèse concerne la calibration intrinsèque d'un C-arm à partir de la détection de la projection du collimateur de la source dans les radiographies.Nous avons développé une méthode de détection de la projection des bords linéaires du collimateur. Elle surpasse les méthodes classiques comme le filtre de Canny sur données simulées ou réelles. La précision que nous obtenons sur l'angle et la position (phi,s) des droites est de l'ordre de: phi{RMS}=+/- 0.0045 degrees et s{RMS}=+/- 1.67 pixels. Nous avons évalué nos méthodes et les avons comparés à des méthodes classiques de calibration dans le cadre de la reconstruction 3D. / Mobile isocentric x-ray C-arm systems are an imaging tool used during a variety of interventional and image guided procedures. Three-dimensional images can be produced from multiple projection images of a patient or object as the C-arm rotates around the isocenter provided the C-arm geometry is known. Due to gravity affects and mechanical instabilities the C-arm source and detector geometry undergo significant non-ideal and possibly non reproducible deformation which requires a process of geometric calibration. This research investigates the use of the projection of the slightly closed x-ray tube collimator edges in the image field of view to provide the online intrinsic calibration of C-arm systems.A method of thick straight edge detection has been developed which outperforms the commonly used Canny filter edge detection technique in both simulation and real data investigations. This edge detection technique has exhibited excellent precision in detection of the edge angles and positions, (phi,s), in the presence of simulated C-arm deformation and image noise: phi{RMS} = +/- 0.0045 degrees and s{RMS} = +/- 1.67 pixels. Following this, the C-arm intrinsic calibration, by means of accurate edge detection, has been evaluated in the framework of 3D image reconstruction.
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Antenas e superf?cies seletivas de freq??ncia reconfigur?veis para sistemas de comunica??o sem fioCosta, Iradilson Ferreira da 11 August 2009 (has links)
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Previous issue date: 2009-08-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to present how the reconfigurable microstrip antennas and frequency selective surfaces can be used to operate at communication systems that require changing their operation frequency according to system requirements or
environmental conditions. The main purpose is to present a reconfigurable circular microstrip antenna using a parasitic ring and a reconfigurable dipole frequency selective
surface. Thereupon there are shown fundamental topics like microstrip antennas, PIN diodes and the fundamental theory of reconfigurable antennas and frequency selective
surfaces. There are shown the simulations and measurements of the fabricated prototypes and it is done an analysis of some parameters like the bandwidth and radiation pattern, for the antennas, and the transmission characteristics, for the
frequency selective surface. Copper strips were used in place of the diodes for proof of the reconfigurability concept / Este trabalho tem como objetivo apresentar como as antenas de microfita e as superf?cies seletivas de frequ?ncia reconfigur?veis podem ser alternativas para operar
em sistemas de comunica??o sem fio que necessitem alterar sua frequ?ncia de opera??o de acordo com os requisitos impostos a este sistema ou condi??es do meio. O prop?sito
central ? apresentar uma antena de microfita com patch circular reconfigur?vel utilizando um anel parasita e uma superf?cie seletiva de frequ?ncia tipo dipolo reconfigur?vel. Para isto s?o apresentados temas fundamentais como as antenas de microfita, diodos PIN e a teoria fundamental de opera??o das antenas e superf?cies seletivas de frequ?ncia reconfigur?veis. S?o apresentadas todas as simula??es e
medi??es realizadas dos prot?tipos constru?dos e ? feita uma an?lise de alguns par?metros como largura de banda e diagrama de radia??o, para as antenas, e caracter?sticas de transmiss?o, para as superf?cies seletivas de frequ?ncia. Foram
utilizadas fitas de cobre no lugar dos diodos para a prova do conceito de reconfigurabilidade
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Expressão de mmp-2, mmp-9 e upar em próstatas caninas normais e c lesões proliferativas / Expression of mmp-2, mmp-9 and uPAR in normal canine prostates c proliferative lesionsFALEIRO, Mariana Batista Rodrigues 02 March 2010 (has links)
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Previous issue date: 2010-03-02 / Humans and dogs show dysplastic lesions in the prostate, such as prostatic intraepithelial neoplasms (PIN) and proliferative inflammatory atrophy (PIA), which are studied due to their malignance potential. The matrix metalloproteinases (MMP) are a family of proteolytic enzymes thought to play an important role in tumor invasion and metastasis in face of their ability to degrade the extracellular
matrix (ECM) and basement membrane. The plasminogen activator (PA) system has been suggested to play a central role in cell adhesion, migration, wound healing, angiogenesis, inflammation, regulation of growth factors and tumor invasion. The receptor of plasminogen activator type activator (uPAR) is a component of the PA, with a range of expression in tumor cell and stromal cells. So, this study was aimed to evaluated the expression and correlation between MMP-2 (gelatinase A) and MMP-9 (gelatinase B) as well as the expression of uPAR in normal canine prostate tissue and also in tissue with proliferative disorders, including benign prostatic hyperplasia (HPB), PIA, PIN and carcinoma. And therefore establish relation among the role of these enzymes in the remodeling of the extracellular matrix (ECM) and in the process of tumor invasion and metastasis. For this, it was performed immunohistochemical staining in tissue microarray of 149 paraffin-embedded fragments of prostate tissue selected from
57 prostates of non-castrated adult dogs with or without prostatic diseases. A total of 298 cores were analyzed and it was made 363 diagnoses: 36 (9.9%) normal, 49 (13.5%) BPH, 132 (36.3%) PIA, 75 (20.7%) PIN and 71 (19.6%) carcinomas. It was observed differences in cytoplasmatic immunohistochemical staining by MMP-2 and MMP-9 antibodies in relation to the cell number and intensity of
labeling of the acinar epithelial and stromal perilobular cells between normal tissue and in those with proliferative disorders. A correlation between MMP-2 and MMP-9
antibodies occurred just in canine prostates with PIA in relation to the number of labeled cells in acinar epithelium and perilobular stroma, as well as, the staining intensity in the perilobular stromal cells. In relation to uPAR, it was observed
differences of immunohistochemical staining of uPAR antibodies in canine prostate. Likewise, there was over expression in dysplastic and neoplasic specimens, but not in normal and benign prostate tissue. A number of epithelial
cells labeled for uPAR showed variation among the diagnoses, except between PIN and carcinoma. Less intensity of labeling was observed in acinar epithelial cells of normal prostates compared with PIA, PIN and carcinoma. However, in the
normal cells and in those with PIA, there was a difference in the number of cells, as well as in the intensity of stromal labeling. The intensity of labeling of stromal perilobular cells was higher in the PIA. PIA-A (accentuated) and PIA-M
(moderated) cells showed greater intensity staining stroma and stromal cells labeled for uPAR, respectively. Thus, this study concludes that there was variation in gelatinases and uPAR expression in canine prostate according to the lesion.
Also, there was Less labeling in normal and BPH and higher in PIA, PIN and carcinoma prostate tissues. The correlation between MMP-2 and MMP-9 in canine prostates with PIA indicates that the inflammation likely influenced the activity of
these enzymes with simultaneous increase in their expression. The uPAR high expression in inflammatory and neoplasic tissues suggests high ECM proteolytic activity in these situations / Nas espécies humana e canina lesões displásicas da próstata, como a neoplasia intra-epitelial prostática (PIN) e a atrofia inflamatória proliferativa (PIA), são estudadas quanto ao potencial de malignidade. As metaloproteinases (MMP) são
enzimas proteolíticas envolvidas no processo de invasão tumoral e metástase, causando destruição de barreiras biológicas como a matriz extracelular (MEC) e a membrana basal (MB). O sistema ativador de plasminogênio (PA) compreende proteínas com ação na adesão celular, regulação da migração, cicatrização, angiogênese, inflamação, regulação de fatores de crescimento e invasão tumoral. O receptor de ativador de plasminogênio tipo uroquinase (uPAR) é um dos componentes do PA, com variação de expressão em células neoplásicas e estromais. Este trabalho teve por objetivo verificar a expressão e a correlação entre MMP-2 e MMP-9, assim como a expressão do uPAR no tecido prostático
canino normal e com alterações proliferativas, incluindo a hiperplasia prostática benigna (HPB), a PIA, a PIN e o carcinoma, buscando avaliar o papel dessas proteínas no remodelamento da MEC e no processo de invasão tumoral e
metástase. Para isso, foi realizada a imunoistoquímica em lâminas de microarranjo tecidual (TMA), com 149 cores selecionadas de 57 próstatas de cães adultos, não castrados, com ou sem histórico de afecções prostáticas. Foram
analisados, para cada anticorpo, 298 cores, perfazendo 363 diagnósticos, sendo 36 (9,9%) normais, 49 (13,5%) HPB, 132 (36,3%) PIA, 75 (20,7%) PIN e 71 (19,6%) carcinomas. Foi possível observar diferença de imunomarcação citoplasmática de MMP-2 e MMP-9 em relação ao número de células e
intensidade de imunomarcação nas células epiteliais acinares e estromais periacinares em relação aos diagnósticos. A correlação entre os anticorpos MMP-2 e MMP-9 ocorreu em próstatas caninas com PIA quanto ao número de células
imunomarcadas no epitélio acinar e no estroma periacinar, bem como quanto à intensidade de imunomarcação nas células estromais periacinares. Quanto ao uPAR, houve diferença na imunomarcação em relação ao diagnóstico, com maior expressão nas displásicas e neoplásicas em relação ás normais e com HPB. O número de células epiteliais imunomarcadas para uPAR variou entre os diagnósticos, exceto entre PIN e carcinoma. Menor intensidade de
imunomarcação epitelial foi constatada nas próstatas normais em relação às com PIA, PIN e carcinoma. Entre as normais e com PIA houve diferença no número de células e intensidade de imunomarcação estromal. A intensidade de imunomarcação estromal foi maior nas com PIA. As PIA-M (inflamação
moderada) e PIA-A (inflamação acentuada) apresentaram maior intensidade de imunomarcação estromal e células estromais imunomarcadas para uPAR, respectivamente. Concluiu-se que há variação na expressão das gelatinases e do uPAR na próstata canina, de acordo com a lesão, com menor expressão nas normais e com HPB e maior naquelas com PIA, PIN e carcinoma. A correlação entre MMP-2 e MMP-9 em próstatas caninas com PIA indica que a inflamação
influencia a atividade dessas enzimas, com aumento simultâneo na expressão de ambas no microambiente inflamatório. Ainda, o aumento na expressão do uPAR nos microambientes inflamatório e neoplásico sugere maior atividade proteolítica na MEC nesses casos
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Měření rozložení optické intenzity ve vzdálené zóně / Measurement of the optical intensity distribution at the far fieldVitásek, Jan January 2009 (has links)
The topic of this master’s thesis is energy measurement of the optical intensity distribu-tion at the far field. Properties of the optical intensity and the optical power are described. In this thesis solution of wave equation is done. The plane wave, spherical wave and Gaussian beam are described. In this thesis, optical trace of laser beam from transmitter laser diode to receiver PIN photodiode is described. One of the solved problems is diffraction on the lens socket. The basic configuration for diffraction investigation on lens socket was created. There were transmitting laser diode, stop with circular apertures and PIN photodiode used in the experiment. In the other part, thesis deals with measuring and detection of the optical beam. Sorts of photodiodes and their characteristics were analysed.
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