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1

Gear, Annabel Jane. "Holocene vegetation history and the palaeoecology of Pinns sylvestris in north Scotland." Thesis, Durham University, 1989. http://etheses.dur.ac.uk/1020/.

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2

Cedergren, Linnéa. "Physics-informed Neural Networks for Biopharma Applications." Thesis, Umeå universitet, Institutionen för fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185423.

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Physics-Informed Neural Networks (PINNs) are hybrid models that incorporate differential equations into the training of neural networks, with the aim of bringing the best of both worlds. This project used a mathematical model describing a Continuous Stirred-Tank Reactor (CSTR), to test two possible applications of PINNs. The first type of PINN was trained to predict an unknown reaction rate law, based only on the differential equation and a time series of the reactor state. The resulting model was used inside a multi-step solver to simulate the system state over time. The results showed that the PINN could accurately model the behaviour of the missing physics also for new initial conditions. However, the model suffered from extrapolation error when tested on a larger reactor, with a much lower reaction rate. Comparisons between using a numerical derivative or automatic differentiation in the loss equation, indicated that the latter had a higher robustness to noise. Thus, it is likely the best choice for real applications. A second type of PINN was trained to forecast the system state one-step-ahead based on previous states and other known model parameters. An ordinary feed-forward neural network with an equal architecture was used as baseline. The second type of PINN did not outperform the baseline network. Further studies are needed to conclude if or when physics-informed loss should be used in autoregressive applications.
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3

Santini, Filippo. "Towards the characterisation of adaptive syndromes of Mediterranean pines: insights through innovative tree phenotyping techniques." Doctoral thesis, Universitat de Lleida, 2020. http://hdl.handle.net/10803/668898.

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En aquesta tesi, es van estudiar patrons de variació genètica intraespecífica en caracters funcionals de Pinus halepensis Mill., Pinus nigra Arnold i Pinus sylvestris L. Un conjunt de tècniques de fenotipat ben establertes van ser combinades amb dades de teledetecció obtingudes amb un dron (unmanned aerial vehicle, UAV). Les imatges d’UAV van indicar una diferenciació genètica en estratègies adaptatives de P. halepensis, determinada per la variació en la disponibilitat d'aigua dins la distribució geogràfica de l’espècie. En P. nigra, la diferenciació genètica va ser determinada per les temperatures mínimes anuals. D'altra banda, la disponibilitat d'aigua va tenir una importància marginal com a determinant de la variació intraespecífica en aquesta espècie. Així mateix es va detectar una escassa diferenciació genètica en P. sylvestris en trets relacionats amb l'ús d'aigua. No obstant això, aquesta espècie va presentar una considerable variació plàstica en l'eficiència de l'ús de l'aigua. La informació proporcionada per aquesta tesi és crucial per comprendre la dinàmica futura d'aquestes espècies i emfatitza la vulnerabilitat de P. nigra i P. sylvestris en el context del canvi climàtic A més, els resultats d'aquesta tesi subratllen l'ús d'imatges derivades d'UAVs com potencials eines de fenotipat massiu en espècies forestals.
En esta tesis, se estudió la variación genética intraespecífica de rasgos funcionales de Pinus halepensis Mill., Pinus nigra Arnold y Pinus sylvestris L., combinando técnicas de fenotipado bien establecidas con datos de teledetección obtenidos un dron (unmanned aerial vehicle, UAV). Las imágenes de UAV revelaron una diferenciación genética en estrategias adaptativas de P. halepensis, determinada por la existencia de poblaciones adaptadas a la sequía. En P. nigra, la diferenciación genética fue determinada por las temperaturas mínimas anuales. Por otro lado, la disponibilidad de agua tuvo una importancia marginal como determinante de la variación intraespecifica en esta especie. Asimismo se detectó una escasa diferenciación genética en P. sylvestris en rasgos relacionados con el uso de agua. Sin embargo, esta especie presentó una considerable variación plástica en la eficiencia del uso del agua. La información proporcionada por esta tesis es crucial para comprender la dinámica futura de estas especies y enfatiza la vulnerabilidad de P. nigra y P. sylvestris en el contexto del cambio climático Además, los resultados de esta tesis subrayan el uso de imágenes derivadas de UAVs como potenciales herramientas de fenotipado masivo en especies forestales.
This thesis studied the intra-specific genetic variation in functional traits of Pinus halepensis Mill., Pinus nigra Arnold and Pinus sylvestris L. by combining well-established phenotyping techniques with remote sensing data obtained with an Unmanned Aerial Vehicle (UAV). UAV-imagery revealed a genetic divergence in adaptive strategies in P. halepensis, related to the presence of drought-adapted populations. In P. nigra, genetic variation was related to winter temperatures, while water availability had a weak role as driver of intra-specific divergence. Similarly, a weak genetic differentiation emerged in P. sylvestris in water-related traits, although this species showed high plastic variation in water use efficiency. The information provided by this thesis is crucial to understand the future dynamics of these pines, highlighting the vulnerability of P. nigra and P. sylvestris in the context of climate change. In addition, this thesis provided a strong support for the use of UAV-derived imagery as phenotyping tool in forest species.
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4

Kuo, Eva Grotkopp. "Genome size evolution, seedling relative growth rate, and invasiveness in pines (Pinus) /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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5

Rautio, Pasi. "Nutrient alterations in Scots pines (Pinus sylvestris L.) under sulphur and heavy metal pollution /." Oulu : Oulun Yliopisto, 2000. http://herkules.oulu.fi/isbn9514257839.

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6

Lara, S. F. "Taxonomy and genetic variation of pinyon pines (Pinus subsection Cemroides) in the northeast of Mexico." Thesis, University of Edinburgh, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.653683.

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The group Pinus subsection Cembroides belongs to section Parrya which, together with section Strobus, forms subgenus Strobus, the haploxylon or “soft pines”. There are 14 taxa recognized for Mexico. Eight (Pinus catarinae, P. cembroides, P. culminicola, P. johannis, P. nelsonii, P. pinceana, P. remota and P. cembroides var. bicolor) occur in the Northeast. Two of these species, P. nelsonii and P. pinceana are highly localized and are clearly defined taxonomically on the basis of cone morphology, whereas the other species are often very difficult to delimit. The aim of this thesis is to use a variety of DNA based techniques to study whether the current taxonomy of the group is correct and to analyse the genetic structure of the species and populations. PCR-RFLP and sequence analysis give some evidence for the separation of P. nelsonii and P. pinceana from the other species of pinyon pines, placing them in a different subsection. This distinction was initially based on morphological characters and is now corroborated by chloroplast DNA analysis. There is insufficient variation in the chloroplast genome to elucidate the relationships among the remaining species, suggesting that they have evolved only recently or that they are not distinct taxa. Random amplified polymorphic DNA markers (RAPD) have been used to investigate the relationship in the 6 remaining taxa. RAPD analysis suggests that P. catarinae is synonymous with P. remota, and that P. johannis should now be treated as P cembroides var. bicolor. Within taxa genetic variation is high and differentiation among populations is low. This suggests that even though species have restricted and isolated distributions gene flow among populations has been sufficient to prevent a dramatic loss of genetic variation.
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Favela, Lara Susana. "Taxonomy and genetic variation of pinyon pines (Pinus subsection Cembroides) in the northeast of Mexico." Thesis, University of Edinburgh, 2004. http://hdl.handle.net/1842/14830.

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8

Clavijo, Érika Manuela Asteria 1986. "Avaliação in vitro da resistência à fratura de raízes dentais fragilizadas reabilitadas com núcleos de preenchimento associados a pinos de fibra de vidro." [s.n.], 2013. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290471.

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Orientador: Caio Cezar Randi Ferraz
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-22T04:14:56Z (GMT). No. of bitstreams: 1 Clavijo_ErikaManuelaAsteria_M.pdf: 12544846 bytes, checksum: e5ccc90481f71cac564a4038b3f3cc5f (MD5) Previous issue date: 2013
Resumo: Este trabalho avaliou in vitro a resistência à fratura de raízes de incisivos bovinos com 3 espessuras de dentina, nas quais, foram cimentados pinos de fibra de vidro com e sem reembasamento com resina composta. 180 raízes bovinas foram padronizadas em 14 mm. Os espécimes foram divididos em 3 grupos de acordo com a espessura da parede dentinária: Grupo1 (G1) = 1 milímetro de espessura (n=60); Grupo 2 (G2): 2 milímetros de espessura (n=60) e Grupo Controle (G3)= raízes sem fragilização (n=60). Os 4 mm apicais dos canais radiculares foram selados com Coltosol® e as raízes foram inseridas em um material de moldagem a base de poliéter e resina acrílica para simulação ligamento periodontal. Em seguida, cada grupo foi subdividido em 2 sub-grupos (n=30): raízes que receberam cimentação de pino de fibra de vidro somente (P) e raízes que receberam cimentação com pino reembasado com resina composta (PR). O cimento Relyx ARC ® foi utilizado para cimentação dos retentores intrarradiculares. Os corpos-de-prova foram submetidos ao teste de resistência à fratura em máquina de ensaio com aplicação de carga em ângulo de 135º com o longo eixo do espécime por lingual (n= 90) e por vestibular (n=90). Os valores foram registrados em Newtons (N) submetidos à Análise de variância e teste de Tukey. As fraturas foram avaliadas em microscópio clínico e classificadas quanto à possibilidade de reabilitação pós-fratura em favoráveis e desfavoráveis. O dado obtido deste estudo mostrou não haver diferença estatística significativa entre os grupos avaliados (p>0,05) com relação ao teste de resistência a fratura com forças aplicadas por vestibular. Por lingual, o grupo G1PR apresentou diferença estatística quando comparado aos grupos G2P e G3P (p<0,05). No teste por vestibular, os espécimes do grupo PR que tiveram fratura radicular, tiveram a incidência de fraturas favoráveis em G1: 87,5%, G2: 80% e G3: 83,3%. Por Lingual, o grupo G3PR apresentou fraturas apenas nos núcleos de preenchimento, não havendo fraturas em raiz. O G1PR e o G1P apresentaram 80% dos espécimes com fraturas radiculares, das quais 91,67% e 66,67% foram classificadas como favoráveis. As diferentes espessuras de dentina não interferiram na resistência à fratura, sugerindo que dentes com paredes fragilizadas são passíveis de serem restaurados. No ensaio realizado por Lingual G1PR apresentou maior resistência a fratura. A maioria das fraturas radiculares, ocorridas nas raízes restauradas com pinos de fibra de vidro e núcleos de preenchimento em resina composta, foram consideradas favoráveis
Abstract: The aim of this is study was to evaluate in vitro fracture strength of weakened roots with 3 thicknesses of dentin, in which were cemented fiberglass posts and anatomic fiber posts (fiberglass post with composite resin). 180 freshly extracted bovine incisors were used. The crowns and apices of were sectioned to create the samples with 14 mm of root. The samples were divided into 3 groups: Group 1 (G1) = dentin walls with 1 mm thickness (n = 60), Group 2 (G2): dentin walls with 2 mm thickness (n = 60) and Control Group (G3) = roots without weakening (n = 60). 4mm apical root canal was sealed with Coltosol ®, and the samples were inserted into artificial periodontal ligament with an impression material and acrylic resin. Then, each group was divided into two subgroups (n = 30) that received roots luting of glass fiber post only (P) and roots receiving cementing anatomic fiber post (PR). The cement Relyx ARC ® was used for cementation of intracanal retainers. The samples were tested for fracture strength in a universal testing machine with load application angle of 135 degrees with the long axis of the specimen by palate (n = 90) and vestibular (n = 90). The values were recorded in Newtons (N) and statistically analyzed by ANOVA. The fractures were evaluated in clinical microscope and classified after fracture as favorable and unfavorable. Results from this study showed no statistically significant difference among the groups (p > 0.05) to the fracture strength test with forces applied by vestibular. On the lingual face there was statistically significant difference between groups G1PR and G1P when compared to CPR (p< 0.05). On the vestibular face the specimens restored with anatomic post that had root fracture from groups G1, G2 and G3 had the incidence of favorable fractures in 87.5%, 80% and 83.3% of the cases. By lingual the CPR group had fractures only in filling cores, with no root fractures. The G1PR and G1P showed 80% of specimens with root fractures, of which 91.67% and 66.67% were classified as favorable. The different thicknesses of dentin did not affect the fracture strength, suggesting that teeth with weakened walls are easily restorable. By Lingual. The anatomic post showed higher resistance to fracture. Most root fractures, when occur in teeth restored with fiberglass posts are considered favorable
Mestrado
Endodontia
Mestra em Clínica Odontológica
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9

Rautio, P. (Pasi). "Nutrient alterations in Scots pines (Pinus sylvestris L.) under sulphur and heavy metal pollution." Doctoral thesis, Oulun yliopisto, 2000. http://urn.fi/urn:isbn:9514257839.

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Abstract In this study, mineral nutrition and its relation to the vigour of Scots pines growing under the influence of sulphur, copper and nickel stress were investigated. This was done by analysing the nutrient status and needle damage of pines along a pollution transect extending from the proximity of a large S, Cu and Ni emitters on the Kola Peninsula to a background area in Finnish Lapland. Additionally, pine seedlings were exposed to Cu and Ni stress in order to gain more detailed information about the mechanisms behind metal stress. The total sulphur concentrations of the youngest needles in the vicinity of the largest point source were about double compared to those in the reference area (< 800 mg in kg of dry needles vs. > 1900 mg kg-1). In the case of Cu and Ni, this difference was close to 100-fold (from 2-3 mg kg-1 to over 250 mg kg-1). While the elevated sulphur concentrations were not attributable to particle deposition, the particles on needle surfaces raised the total concentrations of Cu and Ni occasionally over 1.5-fold compared to the inside concentrations. The Mn and Zn concentrations showed a decreasing trend, whereas K and P slightly increased towards the Monchegorsk smelters. Enhanced needle senescence and tip necrosis were related to high total foliar levels of Cu, Ni and S and low levels of Zn and Mn. Stomatal chlorosis and other discolourations showed a distinct relation to high SO2 levels in the air and also to high foliar concentrations of Ca, Fe, Si and Cl. Particles deposited on needle surfaces did not cause directly visible injuries in pines. In seedlings, Cu and Ni were enriched in roots: the Ni concentration was up to 16-fold and the Cu concentration 6-fold compared to that added into the soil. While Cu was mostly retained in roots, Ni had much easier access to foliage. The effect of metal stress on other nutrients varied between nutrients, plant parts and metals added. Soil analyses from both the field study and the seedling experiment gave mostly a weak estimation about the plant availability of nutrients. Foliar nutrients remained above the deficiency limits in all studies and were hence not the primary cause for the decrease of pine vigour and the consequent growth retardation and forest decline.
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10

Wells, Karen E. "Development of a Laboratory Protocol for the Micropropagation of Monterey Pines (Pinus Radiata), Año Nuevo Stand." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/76.

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Monterey pine (Pinus radiata), a native tree to California and two Mexican islands, is important both ecologically and economically. Outside native stands, Monterey pines are grown for landscaping in California and on plantations around the world. Pitch canker, a disease caused by the fungus Gibberella circinata Nirenberg & O’Donnell (Fusarium circinatum Nirenberg and O'Donnell) is threatening the survival of Monterey pines. The disease currently affects Monterey pines in many parts of the world including the native stands. No effective chemical or biological control is available but some Monterey pines show resistance to the disease. The purpose of this project was to develop a working protocol for producing genetic clones of the resistant pines through micropropagation. These genetic clones will be used for outplanting in places outside the native stands for ornamental and plantation purposes. This project analyzes the results of ten trials with varied parameters and bases the final protocol on the parameters used in the trial that induces the growth of new shoots. The final protocol developed in this project describes, step-by-step, the media preparation for the initiation, plant material collection, surface sterilization of plant material, plating in media and initiation of shoots on explants. The protocol calls for collecting shoot tips with hardened buds that have not yet elongated, then washing the shoot tips in sterile water with Tween 20 for 15 minutes. The shoots tips are then surface sterilized in a 50% bleach solution for 20 minutes. The explants are broken into disks (to minimize damage to the cells) by inserting the tip of a scalpel and tilting it slightly. The initiation media shown to induce growth consists of ½ strength LePoivre basal salt mixture, 5mg/L benzylaminopurine, 3% sucrose and 0.8% agar and is adjusted to a pH of 5.7, then autoclaved for 20 minutes. The explants are inserted into solidified media and incubated in a growth chamber programmed for 16 hours of light and 8 hours of dark with temperatures of 27ºC and 22ºC and light irradiance of 80µEm-2s-1. After 1 month the protocol calls for transferring the growing shoots to elongation media with full LP basal salts and transferring every month. When the number of desired shoots has been reached the forthcoming protocol for rooting can be followed.
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Morais, Jéssika Mayhara Pereira. "Influência do cimento temporário e do protocolo de limpeza do espaço protético para pino de fibra de vidro sobre a resistência de união na dentina radicular do cimento resinoso autocondicionante /." Araraquara, 2018. http://hdl.handle.net/11449/153599.

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Orientador: Milton Carlos Kuga
Resumo: Os objetivos dos estudos foram avaliar os efeitos da cimentação provisória intrarradicular de um pino metálico com cimentos temporários, de composição química diferentes, e analisar a influência da irrigação com agitação ultrassônica passiva (PUI), sobre a resistência de união do cimento resinoso autoadesivo (Relyx U200) na dentina do espaço radicular preparado para pino de fibra de vidro. Noventa raízes unirradiculares de dentes humanos, foram padronizadas com o comprimento de 17,0 mm, a partir do ápice radicular. Os canais radiculares foram instrumentados até o instrumento F5, irrigados a cada troca de instrumento com 5 mL de hipoclorito de sódio a 2,5% e obturados com cimento contendo resina epóxi (AH Plus; Dentsply DeTrey GmbH, Konstanz, GER). Após 7 dias, foi preparado o espaço intrarradicular para pino de fibra de vidro, na extensão de 11mm, a partir da face cervical radicular, com brocas tipo Largo #1 e #2, e dada a conformação final com a broca #2 do sistema White Post DC (FGM, Joinville, SC, BR). No estudo 1, quarenta espécimes foram distribuídos em 4 grupos (n =10), de acordo com o tipo de protocolo de cimentação provisório do pino metálico: G1 (CO), sem a realização prévia da cimentação provisória do pino metálico intrarradicular; G2 (PR), cimentação provisória do pino metálico com o sistema Provy (Dentsply); G3 (RT) cimentação provisória do pino metálico com o sistema Relyx Temp NE (3M) e G4 (TB), cimentação provisória do pino metálico com o sistema Temp Bond NE (... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The aims of this study are to evaluate the effects of temporary intraradicular cementation of a metallic pin with temporary cements made from different chemical composition, and to analyze the influence of agitation with passive ultrasonic irrigation (PUI) on the bond strength of the self-adhesive resin cement (Relyx U200) in the root space dentin prepared for fiberglass pin. Ninety one-root human teeth were standardized with a length of 17.0 mm from the radicular apex. The root canals were instrumented up to instrument F5, irrigated at each instrument change with 5 mL of 2.5% sodium hypochlorite and filled with cement containing epoxy resin (AH Plus; Dentsply DeTrey GmbH, Konstanz, GER). After 7 days, the intraradicular space, 11mm in length, was prepared for the fiberglass pin, from the root cervical face with Largo # 1 and # 2 drills, and given the final conformation with the drill # 2 from White Post DC system (FGM, Joinville, SC, BR). In study 1, forty specimens were distributed into 4 groups (n = 10), according to the type of provisional cementation protocol of the metal pin: G1 (CO), without executing beforehand the provisional cementation of the intraradicular metallic pin; G2 (PR), provisional cementation of the metallic pin with Provy system (Dentsply); G3 (RT) temporary cementation of the metallic pin with Relyx Temp NE (3M) and G4 (TB) system, provisional cementing of the metallic pin with Temp Bond NE system (Sybron Kerr). In all groups, with exception of CO, met... (Complete abstract click electronic access below)
Mestre
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Ramos, Anna Thereza Peroba Rezende. "Efeitos dos protocolos de irrigação durante o preparo do espaço protético sobre a adesão de pino de fibra na dentina radicular /." Araraquara, 2019. http://hdl.handle.net/11449/181219.

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Orientador: Milton Carlos Kuga
Resumo: Objetivo: avaliar a influência do protocolo de irrigação: sem irrigação (WI), com irrigação alternada (AI) ou com a irrigação contínua (CI), em diferentes situações que influência diretamente na qualidade de adesão do pino de fibra de vidro ao substrato dentinário, para isso analisamos presença de resíduos, quantidade de túbulos dentinários abertos; resistência de união do sistema de cimentação na dentina; padrão de fratura da adesão e penetrabilidade dentinária. Material e métodos: raízes de incisivos bovinos foram obturadas, submetidas ao preparo para pino de fibra e distribuídas em grupos, de acordo com o protocolo de irrigação: (WI); (AI) e (CI), e o cimento utilizado (Allcem Core RelyX Ultimate). Após a conclusão do preparo, as raízes foram subdivididos em grupos (n=10), onde foram avaliadas em MEV para avaliar a presença de resíduos, em MEV para incidência de túbulos dentinários abertos na superfície dentinária, Microscopia Confocal a laser para avaliar a penetrabilidade, Estereomicroscopio para avaliar o padrão de fratura. Pinos de fibra foram cimentados com sistema de cimentação (RelyX Ultimate) nos demais espécimes (n=10) e submetidos ao teste de push-out e avaliação do padrão de fratura. Resultados: Em todas as avaliações os grupos que tiveram irrigação contínua no preparo do pino apresentaram valores significativamente melhores em relação ao que estava sendo analisado em especifico (P > 0,05). Os terços cervical e médio também apresentaram melhores resultado compar... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Objective: The aim of this study was to assess the influence of the irrigation protocol: without irrigation (WI), alternate irrigation (AI) or continuous irrigation (CI), in different situations that directly influence the adhesion quality of the fiber post to the dentin substrate, for this we analyzed the residues presence, the number of open dentinal tubules; bonding strength of the cementation system in dentin; adhesion failure pattern and dentin penetrability. Material and methods: roots of bovine were obturated, submitted to preparation for fiber post and distributed in groups, according to the irrigation protocol: (WI); (AI) and (CI), and the cement used (Allcem Core RelyX Ultimate). After the preparation was completed, the roots were subdivided into groups (n = 10), where they were evaluated in SEM to evaluate the residues, in SEM for incidence of open dentinal tubules on the dentin surface, Confocal laser microscopy to evaluate the penetrability, stereomicroscope to evaluate the failure pattern. Posts were cemented with cementation system (RelyX Ultimate) in the other specimens (n = 10) and submitted to the push-out test and evaluation of the failure pattern. Results: In all evaluations, the groups that had continuous irrigation in the preparation of the post showed significantly better values than the one being analyzed in specific (P> 0.05). The cervical and middle thirds also presented better results compared to the apical thirds. Conclusion: WI caused a greater p... (Complete abstract click electronic access below)
Doutor
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Al-Rabab'ah, Moh'd Ali. "Evolutionary dynamics of Pinus taeda L. in the Late Quaternary: An interdisciplinary approach." Texas A&M University, 2003. http://hdl.handle.net/1969.1/1208.

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Pinus taeda L. dynamics, migration patterns and genetic structure were investigated over geological time scale (the past 21,000 years), historical time scale (the past 500 years) and recent time scale (the past 50 years ago) using multi-source data and an interdisciplinary approach. Population genetics, microsatellite markers, DNA fingerprinting, fossil records, geological history, historical records, aerial photographs, soil maps, weather data, remote sensing and geographic information systems (GIS) were used to assess the dynamics of P. taeda populations especially for the Lost Pines (LP), a disjunct population at the westernmost edge of the species range. Pinus taeda populations east and west of the Mississippi River Valley are genetically differentiated. Eastern populations had higher allelic diversity and diagnostic alleles than western populations. Gene flow estimates are high. Allelic diversity and diagnostic alleles patterns are attributed to the prevailing wind direction. Differentiation east and west of the MRV was attributed to separation to two refugia during the Pleistocene. The Lost Pines population is believed to have undergone one or more bottleneck events with loss of rare alleles. Despite the bottleneck, allelic richness was similar for the LP and the control population from the Western Gulf (WG) population. Population size contraction of the LP was attributed to climate change in central Texas over geological time scale. The natural origin of the Lost Pines was investigated. Multivariate and clustering techniques and assignment and exclusion methods using DNA markers show that the LP population shared ancestry with the WG populations with no evidence for admixture from other sources. Historical records parallel this conclusion. With the absence of logging within Bastrop and Buescher State Parks, P. taeda area and patch size increased from 1949 to 1995. Thirty six percent of the pine patches observed in 1949 had disappeared by 1995 by merging. Landscape pattern analysis shows significant dynamics. The distribution of P. taeda in Bastrop County was associated with sandy light topsoils, clayey heavy sub-soils and high permeable soils. Pinus taeda grow on various soil types as well. Growing on these soils under current climatic conditions may compensate for the precipitation regime in this area.
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Smiljanic, Marko [Verfasser], Martin [Akademischer Betreuer] Wilmking, Martin [Gutachter] Wilmking, and Achim [Gutachter] Bräuning. "Growth responses of peatland pines : can peatland Scots pines (Pinus sylvestris) be used as dendroecological proxies to peatland hydrology and environment? / Marko Smiljanic ; Gutachter: Martin Wilmking, Achim Bräuning ; Betreuer: Martin Wilmking." Greifswald : Universität Greifswald, 2019. http://d-nb.info/1199537683/34.

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Pontes, Danielson Guedes 1977. "Técnicas para cimentação de pinos de fibra de vidro = avaliação da resistência adesiva, nanoinfiltração e influência da clorexidina." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289630.

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Orientador: Luis Alexandre Maffei Sartini Paulillo
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo foi investigar a resistência de união entre pinos de fibra de vidro/dentina radicular através de "push-out" e nanoinfiltração, e ainda, a influência da solução irrigadora do canal radicular - clorexidina 2% - na qualidade da adesão de cimentos auto-adesivos. Método: Para o desenvolvimento deste estudo foram realizados dois experimentos. Noventa e oito raízes bovinas foram utilizadas no teste de push-out (n=10) e dezoito raízes foram separadas para a análise da nanoinfiltração (n=3) na interface de pinos de fibra de vidro cimentados com diferentes materiais, que foram divididas em 6 grupos: RelyX Unicem (UNC); RelyX U100 (UCE); Scothbond Multiuso Plus ativação química + RelyX CRA (ASR); Scothbond Multiuso Plus ativação física + RelyX CRA (SBR); Clearfil SE Bond/ED Prime + Panavia F 2.0 (CEP); Clearfil SE Bond + Panavia F 2.0 (CFP). Os pinos foram cimentados no canal radicular de acordo com as recomendações de cada fabricante. Para o ensaio de push-out, foram obtidas fatias com 1,0 mm de espessura dos terços cervical, médio e apical de cada raiz, e o teste foi conduzido em máquina de ensaio universal na velocidade de 0,5 mm por minuto. Para a análise da nanoinfiltração, as fatias foram imersas em solução de nitrato de prata amoniacal (AgNO3) para a microscopia eletrônica de varredura (MEV). Posteriormente, para a an lise da influência do digluconato de clorexidine na resistência à união e nanoinfiltração de cimentos auto-adesivos, foram formados 4 grupos: RelyX Unicem (UNC); RelyX U100 (UCE); Clorexidine 2% + RelyX Unicem (UNX); Clorexidine 2% + RelyX U100 (UCX). Os resultados foram analisados através de análise de variância com parcela subdividida (p<0,05). Resultados: Sistemas de fixação: Entre as técnicas de cimentação, no terço médio, o S mostrou a maior resistência com diferença estat stica para os sistemas EP, FP e UN . Somente o grupo FP apresentou diferença estat stica significativa entre os terços radiculares, com menor resultado no terço apical quando comparado ao terço cervical. No terço cervical, a menor média foi do grupo S apresentando diferença estat stica significativa para o grupo S . Nanoinfiltração: No terço apical o CFP apresentou a maior nanoinfiltração com diferença estatística significativa para os terços médio e cervical, e também para os outros sistemas. Clorexidina: O uso da clorexidina como solução irrigadora do canal radicular diminuiu significativamente a resistência adesiva dos cimentos auto-adesivos. Em todos os grupos houve a presença de nanoinfiltração e na interface adesiva e não foi observada a formação de camada híbrida. Conclusão: O uso de sistemas adesivos que empregam prévio condicionamento ácido e possuem ativação química possibilitou melhores resultados de resistência à união e melhor qualidade da camada híbrida. O uso de ativador químico para o sistema adesivo autocondicionante, permitiu melhora significativa da união na região mais profunda da raíz. A irrigação prévia do canal radicular com clorexidine 2% influenciou negativamente a resistência adesiva dos cimentos auto-adesivos
Abstract: The aim of this study was to investigate the bond interface between glass fiber post/root dentin by means of push-out and nanoleakage tests, as well as the influence of the root canal irrigant solution - 2% chlorhexidine - on the bond quality of self-adhesive cements. Methods: In order to develop this study two analysis were performed. Bovine roots were used in the push-out test (n=10) and eighteen roots were separated for analysis of nanoleakage (n=3) at the interface of glass fiber posts cemented with different adhesive techniques, which were divided into six groups: RelyX Unicem (UNC); RelyX U100 (UCE); Scotchbond Multipurpose chemical activation + RelyX ARC (ASR); Scotchbond Multipurpose physical activation + RelyX ARC (SBR); Clearfil SE Bond / ED Prime + Panavia F 2.0 (CEP); Clearfil SE Bond + Panavia F 2.0 (CFP). The posts were cemented in the root canal in accordance with the recommendations of each manufacturer. For the push-out test 1.0 mm thick slices were obtained of the cervical, middle and apical thirds of each root, and the test was conducted in a universal test machine at a speed of 0.5 mm per minute. To analyze nanoleakage, the disc-shaped specimens were immersed in ammoniacal silver nitrate solution (AgNO3) for scanning electron microscopy (SEM). Subsequently, to analyze the influence of 2% chlorhexidine digluconate in bond strength and nanoleakage of the self-adhesive cements, were formed four groups: RelyX Unicem (UNC); RelyX U100 (UCE); 2% Chlorhexidine + RelyX Unicem (UNX); 2% Chlorhexidine + RelyX U100 (UCX). The results were analyzed using analysis of variance with subdivided parcel (p<0.05). Results: Fixation Systems: Among the cementation techniques in the middle third, ASR showed the highest bond strength with statistical difference from the CEP, CFP and UNC systems. Only CFP presented statistically significant difference between the roots thirds, with the lower result in the apical third compared with the cervical third. In the other groups there was no significant difference among the different root thirds. In the cervical third, the lowest mean was obtained by SBR presenting statistically significant difference from ASR. Nanoleakage: In the apical third CFP presented the greatest nanoleakage with statistically significant difference from the middle and cervical thirds, and also from the other systems. Chlorhexidine: The use of chlorhexidine as root canal irrigant solution significantly reduced the bond strength of the self-adhesive cements. There was nanoleakage at the adhesive interface and hybrid layer formation was not observed, in all groups. Conclusions: The use of adhesive systems that use previous acid etching and are chemical setting enables better adhesive bond strength and better hybrid layer quality to be obtained. The use of chemical activator for the self-etching system allowed a significant improvement of the bond in the deepest region of the root. Prior root canal irrigation with 2% chlorhexidine negatively influenced the bond strength of self-adhesive cements
Doutorado
Dentística
Doutor em Clínica Odontológica
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16

Plourde, Annie. "Croissance, développement et architecture des structures aériennes et souterraines de pins gris (Pinus banksiana Lamb.) dans un peuplement naturel et une plantation /." Thèse, Chicoutimi : Montréal : Université du Québec à Chicoutimi ; Université du Québec à Montréal, 2007. http://theses.uqac.ca.

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Thèse (D.Sc.Env.) -- Université du Québec à Chicoutimi, 2007.
La p. de t. porte en outre: Thèse présentée à l'Université du Québec à Chicoutimi et l'Université du Québec à Montréal comme exigence partielle du doctorat en sciences de l'environnement. CaQCU Bibliogr.: f. 140-141. Document électronique également accessible en format PDF. CaQCU
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17

Antonelli, Priscilla de Oliveira. "Estaquia de matrizes adultas de Pinus elliottii var. elliottii e Pinus elliottii x Pinus caribaea." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-11092013-173126/.

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O Pinus elliotti representa o principal produtor atual de exploração de resina no setor florestal brasileiro. Recentemente, plantios de P. elliottii X P. caribaea vêm se destacando, principalmente, pela sua maior produtividade em biomassa. Além disto, a resina do híbrido apresenta características químicas semelhantes aos seus parentais. Porém, poucas são as informações quanto a estaquia de espécies do gênero Pinus, e se focarmos na propagação de árvores adultas, tal carência é ainda maior, principalmente ao se considerar a dificuldade de rejuvenescimento/revigoramento do material genético. Neste contexto, o presente trabalho teve como objetivo geral avaliar o enraizamento adventício do P. elliottii var. elliottii e P. elliottii X P. caribaea adultos. Para tanto, o trabalho foi dividido em três diferentes estudos. O primeiro (Capítulo 2) avaliou o enraizamento adventício de estacas das matrizes adultas de P. elliottii e P. elliottii X P. caribaea no 5° estágio de enxertia seriada com e sem podas sucessivas, sob ação do AIB, talco com fungicida Cerconil® e terebentina. O segundo (Capítulo 3) foi baseado na avaliação do enraizamento adventício de estacas no 2° estágio de enxertia seriada de uma matriz adulta de P. elliottii var. elliottii submetida a um ano de podas sucessivas, sob ação do AIB, terebentina e paclobutrazol. Por sua vez, o terceiro estudo (Capítulo 4) consistiu na avaliação do enraizamento adventício de braquiblastos e brotos de duas matrizes adulta de P. elliottii e P. elliottii X Pinus caribaea, sob ação do AIB e paclobutrazol. Os resultados permitiram inferir que a sobrevivência e o enraizamento adventício aos diferentes tratamentos variaram de acordo com o genótipo e com as características morfológicas das estacas (grau de lignificação e tipo de estacas, brotos e braquiblastos). De maneira geral, os resultados evidenciaram a atuação das enxertias seriadas e das podas sucessivas na restauração da competência rizogênica das estacas dos brotos das matrizes adultas de P. elliottii e P. elliottii X P. caribaea, promovido pelo rejuvenescimento/ revigoramento parcial das matrizes. Além disto, a estaquia de braquiblastos mostrou ser uma ferramenta promissora para a propagação de espécies do gênero Pinus.
Pinus elliottii is the main current resin extraction producer in the Brazilian forest sector. Recently, plantations of P. elliottii X P. caribaea play a great importance in the production systems mainly by its high biomass productivity. In addition, the hybrid resin has chemical characteristics similar to their parents. However, there is little information on obtaining clones, and considering the propagation of mature trees, this lack of information is even greater, mainly concerning the difficulty to achieve the rejuvenation/ reinvigoration of the genetic material. Based on theses information, the present work was aimed to evaluate the adventitious rooting of mature P. elliottii var. elliottii and P. elliottii X P. caribaea cuttings. Therefore, the work was divided into three basic studies. The first study (Chapter 2) was based on the evaluation of adventitious rooting of mature P. elliottii and P. elliottii X caribaea cuttings of grafts up five sequential grafting with and without pruning, under the action of AIB, talc with fungicide and turpentine. The second (Chapter 3) was based on the evaluation of adventitious rooting of mature P. elliottii cuttings of grafts up two sequential grafting with pruning, under the action of IBA, paclobutrazol and turpentine. The third (Chapter 4) evaluated the adventitious rooting of brachyblast and shoots of mature P. elliottii and P. elliottii X caribaea cuttings, under the action of IBA and paclobutrazol. Results showed that the cutting survival and root growth, under the action of different treatments, varied according to the genotype and morphological characteristics of the material (cutting lignifications and type, brachyblast or shoot). Overall, our results showed the performance of serial grafting and pruning on the restoration of rooting competence in P. elliottii and P. elliottii X P. caribaea stem cuttings, promoted by the rejuvenation of trees. Moreover, the cutting of brachyblast can be a promising tool for the propagation of Pinus species.
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Scarpati, Alexander Otto Eduardo Kraul. "Resistência à fratura de técnicas de colagem empregadas para restauração de dentes fraturados com ou sem tratamento endodôntico." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/23/23134/tde-02012008-115212/.

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O objetivo deste estudo foi comparar à resistência à fratura de três técnicas de colagem usadas para restaurar dentes fraturados hígidos e com tratamento endodôntico associado ou não a colocação de pino de fibra de vidro. Noventa incisivos humanos foram aleatoriamente divididos em três grupos de 30 dentes cada. No grupo A, os dentes não foram tratados endodonticamente, enquanto os dentes dos grupos B e C foram submetidos ao tratamento endodôntico, seguido de restauração da câmara pulpar com resina composta. Todos os dentes foram fraturados por uma carga axial aplicada na superfície vestibular para obter fragmentos dentais. Os dentes de cada grupo foram novamente subdivididos em três subgrupos: colagem simples [CS], chanfro vestibular [CV] e chanfro circunferencial [CC]). Antes da colagem dos fragmentos, pinos de fibra de vidro foram colocados nos dentes do grupo C. Todos os fragmentos dos dentes (grupos A, B e C) foram colados utilizando um cimento de dupla ativação (Duo- Link, Bisco Inc). No grupo CS, nenhum preparo adicional foi realizado após colagem, porém no restante dos dentes realizou-se uma canaleta vestibular (grupo CV) ou uma canaleta circunferencial ao redor da linha de colagem (CC) com aproximadamente 1,0 mm de profundidade. As canaletas foram restauradas com resina composta microhíbrida. Por fim, os espécimes foram submetidos a mesma carga axial no mesmo ponto pré-determinado. A resistência à fratura após o procedimento restaurador foi expressa em porcentagem de resistência do dente íntegro. Os dados foram submetidos a uma análise de variância de dois fatores (Grupo vs. Técnica de colagem) e teste de Tukey (?=0,05). Somente o fator principal Técnica de colagem foi estatisticamente significante (p<0,05). Nenhuma das técnicas de colagem empregadas conseguiu restabelecer a resistência à fratura do dente hígido. A confecção de uma canaleta vestibular e circunferencial proporcionaram uma recuperação de resistência similar (p>0,05) entre si e superior ao alcançado pela técnica de colagem simples (p<0,05). Concluiu-se que o uso de pino de fibra de vidro não é essencial para reforço da estrutura dental antes da colagem de fragmentos de dentes tratados endodonticamente. As técnicas de chanfro vestibular e chanfro circunferencial devem ser preferidas ao se realizar a colagem de fragmentos devido a maior recuperação da resistência do dente hígido em relação a técnica de colagem simples.
The aim of this study was to compare the fracture strength of three techniques used to reattach tooth fragments in sound and endodontically-treated fractured teeth either associated or not with fiber post placement. Ninety human lower incisors were randomly divided into three groups of 30 teeth each. In group A teeth were not subjected to endodontic treatment; while teeth from groups B and C were endodontically treated and the pulp chamber restored with a composite resin. All teeth were fractured by an axial load applied to the buccal area in order to obtain tooth fragments. Teeth from each group were divided again into three subgroups: bonded only [BO], buccal chamfer [BC] and circumferential chamfer [CC]). Before the re-attachment procedures, fiber posts were placed in teeth from group C. All teeth (groups A, B and C) had the fragments re-attached using a dual cure resin luting cement (Duo-Link, Bisco Inc., Itasca, IL). In the BO group, no additional preparation was made. Teeth from groups BC and CC groups had a 1.0 mm-depth chamfer placed in the fracture line either on buccal surface [group BC] or along the buccal and lingual surfaces [group CC]. Increments of microhybid composite resin were used in subgroups BC and CC to restore the chamfer. The specimens were loaded until fracture in the same pre-determined area. The force required to detach each fragment was recorded and a percentage of fracture strength recovery calculated for each tooth. The data was subjected to a two-way analysis of variance (Group vs. Re-attachment technique) and Tukey\'s test (?=0.05). Only the main factor Re-attachment technique was statistically significant (p<0.05). None of the techniques used for teeth re-attachment restored the fracture strength of the intact teeth. The placement of buccal and circumferential chamfer yielded statistically similar (p>0.05) fracture strength recovery, which was superior to the bonded only technique (p<0.05). The use of fiber post is not mandatory for the reinforcement of the tooth structure before reattachment of fragments in endodontically-treated teeth. When bonding a fractured fragment, the buccal or circumferential re-attachment techniques should be preferable in comparison with the simple re-attachment without any additional preparation.
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Bolte, Constance E. "NICHE CONSERVATISM OR DIVERGENCE: INSIGHTS INTO THE EVOLUTIONARY HISTORIES OF Pinus taeda, Pinus rigida, AND Pinus pungens." VCU Scholars Compass, 2017. http://scholarscompass.vcu.edu/etd/4842.

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Environmentally related selective pressures and community interactions are well-documented drivers for niche differentiation, as natural selection acts on adaptive traits best fit for survival. Here, we investigated niche evolution between and within Pinus taeda, Pinus rigida, and Pinus pungens and sought to identify which climate variables contributed to species divergence. We also sought to describe niche differentiation across genetic groupings previously identified for P. taeda and P. rigida. Ecological niche models were produced using Maximum Entropy followed by statistical testing based on a measure of niche overlap, Schoener’s D. Both niche conservatism and niche divergence were detected, thus leading us to conclude that directional or disruptive selection drove divergence of the P. taeda lineage from its ancestor with P. rigida and P. pungens, while stabilizing selection was associated with the divergence of P. rigida and P. pungens. The latter implies that factors beyond climate are important drivers of speciation within Pinus.
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Chaves, Larissa Pinceli. "Efeito de inibidores da atividade proteolítica na resistência de união de pino de fibra de vidro à dentina radicular após 12 meses." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/25/25148/tde-03042017-174435/.

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O estabelecimento de uma camada híbrida adequada no canal radicular representa um dos principais desafios clínicos devido à dificuldade de acesso. Dessa forma, o uso de inibidores proteolíticos poderia tornar-se um recurso favorável. O objetivo deste estudo foi avaliar o efeito de inibidores proteolíticos na união de pino de fibra de vidro fixado com cimento adesivo, considerando os terços radiculares e tempos distintos, por meio da resistência de união (RU). Cento e quarenta e quatro raízes bovinas foram selecionadas e divididas em 6 grupos de tratamento, e redivididas em 3 subgrupos de acordo com os tempos de avaliação de 24 horas, 6 e 12 meses (n=8). Após o tratamento endodôntico e desobturação padronizados, as raízes foram cimentadas com pinos de fibra de vidro cônicos (Exacto/Angelus). As raízes foram tratadas com sistema adesivo convencional de três passos, Adper Scotchbond Multipurpose/ 3M ESPE (SBMP) e cimento dual RelyX ARC/ 3M ESPE. Após prévia divisão, foram alocadas em grupos CN (Controle Negativo- sem pré tratamento associado), CP (Controle Positivo- com agentes ativador e catalisador), EDTA (ácido etilenodiamino tetra-acético a 17%), CHX (digluconato de clorexidina a 2%), E-5 (E- 64 a 5 M) e E-10 (E-64 a 10 M). Após 24 horas, as raízes foram seccionadas perpendicularmente ao longo eixo e identificadas quanto à região, obtendo-se fatias de 1 mm de espessura (cervical, médio e apical), que foram armazenadas em saliva artificial para serem testadas. Todas as fatias foram submetidas ao teste de extrusão (push-out) na máquina de teste universal (Instron) com célula de carga de 50 N a 0,5 mm/min. Os dados foram analisados pelo teste de ANOVA a três critérios e comparações múltiplas com Tukey, ambos com p<0,05. Após 24 horas, não se observou diferenças entre os tratamentos. Após 6 meses, a CHX demonstrou melhor desempenho, cujo efeito não se prorrogou até os 12 meses. O uso de inibidores proteolíticos não foram capazes de preservar a resistência de união dos pinos intrarradiculares até o tempo de 12 meses.
The adequate establishment of hybrid layer in the root canal on bonding process is still a clinical challenge due to its hard access. Thus, the use of proteolytic inhibitors could become a favorable tool. The aim of this study was to evaluate the effect of proteolytic inhibitors in the bonding of a glass- fiber post fixed with a luting cement, regarding the root thirds and different times through the bond strength. One hundred and forty four bovine roots were selected and divided into 6 treatment groups, and subdivided according to the time of evaluation of 24 hours, 6 and 12 months (n=8). After endodontic treatment and standardized removal procedure, the roots were cemented with tapered glass fiber posts (Exacto/ Angelus). The roots were treated with three-step etch-and-rinse adhesive system Adper Scotchbond Multipurpose/ 3M ESPE (SBMP) and dual cement RelyX ARC/ 3M ESPE. After previous division, CN (negative- control without pre associated treatment), CP (Control positive- with activator and catalyst agents) EDTA (17% ethylenediaminetetraacetic acid) CHX (2% chlorhexidine digluconate) E-5 (5M E-64) and E-10 (10M E-64). After 24h, the roots were sectioned perpendicular to the long axis and identified according to third in 1mm thick slices (cervical, middle and apical), which were stored in artificial saliva to be tested. All slices were subjected to extrusion tests (push-out) in the universal test machine (Instron) at 50 N load cell at 0.5 mm/min. Data were analyzed with three-way ANOVA and multiple comparisons with Tukey test, both with p <0.05. After 24 hours, no differences were observed between treatments. After 6 months, CHX showed better performance, which did not last up 12 months. The proteolytic inhibitors performed differently in the bonding process over time; only CHX promoted inhibition at 6 months. The use of proteolytic inhibitors were not able to maintain the bond strength of intraradicular posts up time of 12 months.
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21

Jones, Christoper, and Jack Kelly. "Pines of Arizona." College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2013. http://hdl.handle.net/10150/298136.

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22

Mondeil, Fanjavola. "Contribution à l'amélioration génétique de Pinus kesiya Royle ex. Gordon : morphogénèse, hybridation interspécifique avec Pinus elliottii Engelm. var. elliottii, multiplication végétative." Paris 11, 1987. http://www.theses.fr/1987PA112114.

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Ce travail apporte des bases scientifiques au programme d'amélioration des pins à Madagascar, en abordant le double aspect de la génétique et de la morphogenèse. L'étude du développement morphogénétique et de la croissance de Pinus kesiya Royle ex. Gordon et de Pinus elliottii Engelm. Var. Elliottii permet d'établir des modèles de croissance et les normes de comportement des deux espèces. Modèles et normes ont servi de références à l'étude du comportement des hybrides et à la recherche de critères juvéniles pour une sélection précoce. L'hybridation interspécifique réciproque en polycross entre les de x espèces cherche à associer la plasticité de P. Kesiya à la rectitude du fût et la finesse des branches de P. Elliottii. Les taux moyens de succès de l'hybridation sont de 3,40% lorsque P. Kesiya est pris comme parent femelle; de 10,18% dans le croisement réciproque. Une grande variabilité génétique existe à l'intérieur et entre les 15 familles hybrides interspécifiques. L'effet provenance y est effacé, alors qu'il est élevé chez les 24 familles intraspécifiques. Un effet marqué et prolongé du génotype maternel sur les phénotypes empêche une sélection trop précoce. Mais à 30 mois, les effets paternels s'expriment progressivement. Les hybrides ont des caractères intermédiaires entre les parents. Diamètre du tronc à 1,30m et diamètre des branches sont des prédicteurs fiables du comportement de l'arbre à 66 mois (r = 0,934). A cet âge l'arbre a déjà atteint une hauteur moyenne de 7m. Des estima ions d'héritabilité au sens strict ont été calculées pour 19 caractères mesurés en forêt. Le bouturage des brachyblastes des hybrides réussit dans 67 à 73% des cas. Les ortets de 54 mois donnent des sujets bouturés dont la croissance en hauteur ne diffère pas significativement de celle des sujets issus d'ortets plus jeunes.
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Menezes, Murilo de Sousa. "Protocolo de tratamento de superficie de pino de fibra de quartzo com H2O2." [s.n.], 2009. http://repositorio.unicamp.br/jspui/handle/REPOSIP/289703.

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Orientador: Luis Roberto Marcondes Martins
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: O objetivo deste estudo foi avaliar a resistência de união entre pinos de fibra de quartzo e resina de preenchimento, preliminarmente em função do uso do silano isoladamente e silano associado ao adesivo. Em seguida, em função do condicionamento de superfície do pino com peróxido de hidrogênio (H2O2), variando a concentração (24 e 50%) e o tempo de aplicação (1, 5 e 10 min). Propôs-se também, avaliar qualitativamente, por meio de Microscopia Eletrônica de Varredura (MEV), a morfologia de superfície dos pinos tratados com H2O2 em diferentes protocolos de aplicação, comparativamente ao pino sem nenhum tratamento de superfície. Para avaliar a resistência de união 80 pinos de fibra de quartzo (AESTHETI-PLUS, Bisco) foram divididos, aleatoriamente, em oito grupos (n=10): inicialmente, foram testados (G1) tratado apenas com silano e (G2) tratado com silano e adesivo, para definição do grupo controle. Os grupos experimentais (G3) tratado com H2O2 a 24% por 1 min; (G4), H2O2 a 24% por 5 min; (G5), H2O2 a 24% por 10 min; (G6), H2O2 a 50% por 1min; (G7), H2O2 a 50% por 5 min e (G8), H2O2 a 50% por 10 min. Em seguida, todos os grupos experimentais receberam aplicação de uma camada de silano (PORCELAIN PRIMER, Bisco) e outra de adesivo (ALL BOND 2, Bisco). Em seguida as restaurações em resina composta (CORE-FLO, Bisco) foram simuladas utilizando moldes de silicones. Após 24h de armazenagem em água a 37ºC, as amostras foram submetidas a cortes seriados, perpendiculares ao longo eixo do pino, obtendo amostras com dimensões de aproximadamente 1x1mm, com formato de palito e constituída por resina/pino/resina. As amostras foram submetidas ao ensaio mecânico de microtração à velocidade de 0,5 mm/min até o rompimento dos espécimes. Para análise em MEV, 14 pinos foram divididos em sete grupos (n=2): G1 (controle) sem tratamento nenhum; e os outros seis grupos receberam o mesmo tratamento de superfície com H2O2 correspondente as amostras do ensaio de microtração, entretanto, sem aplicação de silano e adesivo. Os dados de resistência de união apresentaram distribuição normal e homogênea e foram submetidos ao teste t-Student para comparar o grupo G1 ao G2. Os resultados mostraram que G2 apresentou valor de resistência de união significantemente superior ao G1, sendo então considerado como controle para posterior comparação aos grupos experimentais. Em seguida, para comparar entre si os grupos tratados com H2O2, foi aplicada análise de variância fatorial ANOVA (3x2). Foi também realizado Post Hoc Tests Dunnett, para comparação do grupo controle (G2) aos grupos experimentais (tratados com H2O2) em análise de fator único. Os resultados demonstraram que os grupos experimentais apresentaram valores de resistência de união semelhantes entre si e superiores ao controle (G2). As imagens de MEV demonstraram que o tratamento de superfície com H2O2 remove parcialmente a resina epóxica dos pinos expondo as fibras de quartzo. Conclui-se que o H2O2 altera a morfologia de superfície dos pinos de fibra de vidro e aumenta a resistência de união entre o pino e resina de preenchimento.
Abstract: Coupling of fiber posts to composites is hampered by absence of chemical union between epoxy-based resins. This study analyzed the effect of surface treatments of glass fiber posts on bond strength to resin cores. A total of 94 fiber posts (AESTHETI-PLUS, Bisco) were randomly divided into eight groups, according to the surface pre-treatments performed (n=10): (G1), silanization; (G2), silanization and adhesive. Six experimental groups: (G3) 24% hydrogen peroxide (H2O2) for 1 min; (G4), 24% H2O2 for 5 min; (G5), 24%H2O2 for 10 min; (G6), 50% H2O2 for 1min; (G7), 50% H2O2 for 5 min and (G8), 50% H2O2 for 10 min. This was followed by silanization (PORCELAIN PRIMER, Bisco) of the exposed quartz fiber to enhanced their chemical bonding to core composite and application of bonding agent (ALL BOND 2, Bisco). Two posts of each experimental group and two posts without the treatment were investigating the morphologic aspect surface post. The composite resin (CORE-FLO, Bisco) was used for the core build-up in ten remaining posts of each group. The samples were cut so as to obtain microtensile sticks that were loaded in tension at cross-heat speed of 0,5mm/min until failure. Data were statistically analyzed. SEM examination showed pretreatment with H2O2 modifying the fiber post surface. The post-core strengths achieved in G2 were significantly higher, that G1. The experimental groups G3, G4, G5, G6, G7 and G8 were similar and significantly higher, that G2. In conclusion the adhesive and silane enhanced the interfacial strength between them and core material. The hydrogen peroxide modified the surface morphology of fiber post and also significantly enhanced the interfacial strength between them and core material.
Doutorado
Dentística
Doutor em Clínica Odontológica
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24

Pinto, Martina Gerlane de Oliveira. "Detecção de fraturas radiculares em imagens de tomografia computadorizada de feixe cônico utilizando diferentes parâmetros de exposição e materiais intracanais." Universidade Estadual da Paraíba, 2015. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2605.

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The aim of this study was evaluated the detection of radicular fractures (FRs) in Cone Beam Computed Tomography (CBCT) by different exposure parameters and investigate the influence of gutta percha, metal post and fiberglass post in FRs detection and CBCT artifacts formation. One hundred and sixty teeth were selected and divided into four groups according to the filling material: without gutta percha, metal post and fiberglass post. Each group contained experimental teeth that were fractures were induced artificially, and teeth without fracture (controls). All teeth were coated with wax and after they were positioned in the alveolus of a right superior central incisive of a dry human dentate maxilla. The tomographic images were acquired using Kodak 9000 3D machine (Kodak Dental Systems, a Carestream Health, Rochester, NY, EUA) according to the exposure protocols: 1 - 74 kV, 12 mA; 2- 74 kV, 10mA; 3- 74 kV, 8 mA; 4 - 74 kV , 6,3mA; 5 - 70kv,12 mA; 6 - 70kV, 10 mA; 7 - 70 kV , 8 mA; 8- 70 kV, 6,3 mA. Two radiologists analyzed the tomographic images and scored them for fracture detection and artefact interferences. The kappa test intra and inter was calculated for fracture diagnosis (0.87-0.90 and 0.88) and for analysis of the formation of artifacts (0.96-0.98 and 0.95). Statistical analyzes were performed using ANOVA to calculate the sensitivity, specificity and diagnostic accuracy of the test; Chi-square test to compare the expected frequencies of the observed frequencies between CBCT with the gold standard, and logistic regression to observe the influence of intracanal materials in the diagnosis of fracture. Specificity values were higher than the sensitivity for each intracanal material. The sets of exposure parameters showed no significant differences in the detection of fractures. However, there were differences between the materials used intracanal showing the teeth without filler material and glass fiber core exhibited better results compared to teeth with gutta-percha and the metal core. Therefore, it is concluded that viewing of the FRs showed better results when the root canal was empty or filled with fiberglass pin. However, gutta-percha and the molten metal pin were associated with higher artifact formation, which committed an accurate diagnosis.
O objetivo deste estudo foi avaliar a detecção de fraturas radiculares (FRs) em imagens de Tomografia Computadorizada de Feixe Cônico (TCFC) utilizando diferentes parâmetros de exposição e analisar a influência da guta- percha, do núcleo metálico fundido e do pino de fibra de vidro no diagnóstico das FRs, assim como a formação de artefatos em TCFC. Cento e sessenta dentes foram selecionados e divididos em quatro grupos de acordo com o material de preenchimento (sem guta-percha, com guta-percha, pino metálico fundido e pino de fibra de vidro). Cada grupo continha dentes experimentais que foram induzidos artificialmente à fratura e dentes sem fratura como controles. Todos os dentes foram revestidos por cera 7 e posicionados no alvéolo de um incisivo central superior direito em uma maxila dentada de um crânio humano seco. As imagens tomográficas foram adquiridas pelo aparelho da Kodak 9000 3D (Kodak Dental Systems, a Carestream Health, Rochester, NY, EUA) e digitalizadas seguindo os protocolos com parâmetros de exposição 1 - 74 kV, 12 mA; 2- 74 kV, 10mA; 3- 74 kV, 8 mA; 4 - 74 kV , 6,3mA; 5 - 70kv,12 mA; 6 - 70kV, 10 mA; 7 - 70 kV , 8 mA; 8- 70 kV, 6,3 mA. Em seguida, dois radiologistas analisaram as estruturas dos materiais intracanais e estabeleceram escores tanto para o diagnóstico de fratura bem como a análise do grau de interferências dos artefatos. O teste kappa intra e interexaminador foi calculado para o diagnostico de fraturas (0.87-0.90 e 0.88) e para analises da formação dos artefatos (0.96-0.98 e 0.95). Os testes estatísticos utilizados foram ANOVA para calcular os valores de sensibilidade, especifidade e acurácia do teste de diagnostico; teste qui-quadrado para comparar as frequências esperadas das frequências observadas entre a TCFC com o padrão ouro, e regressão logística para observar a influencia dos materiais intracanais no diagnóstico de fratura. Os valores de especificidade foram maiores do que a sensibilidade para cada material intracanal. Os conjuntos de parâmetros de exposição não apresentaram diferenças significativas na detecção de fraturas. No entanto, houve diferenças entre os materiais intracanais utilizados, mostrando que os dentes sem material de preenchimento e com núcleo de fibra de vidro apresentaram melhores resultados comparados com dentes com guta-percha e núcleo metálico. Portanto, conclui-se que a visualização das FRs apresentou melhores resultados quando o canal radicular estava vazio ou preenchido com pino de fibra de vidro. Contudo, a guta-percha e o pino metálico fundido foram associados com maior formação de artefato, o que comprometeu um diagnóstico preciso.
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25

Figueiredo, Mariana Diehl [UNESP]. "Influência de soluções irrigadoras na resistência adesiva de pinos de fibra de vidro utilizando cimento resinoso: avaliação através do teste de push-out." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/90376.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Atualmente, os pinos de fibra de vidro têm surgido como uma alternativa para restaurar dentes tratados endodonticamente. Entretanto, a perda da retenção do pino é uma das principais causas de falhas. Portanto, o objetivo deste estudo foi avaliar a resistência de união e o tipo de falha adesiva, em diferentes regiões da raiz, de pinos de fibra de vidro transparente cimentados no canal radicular com cimento de cura dual, variando-se a solução irrigadora utilizada durante o preparo dos canais, através do teste de push-out. Para o estudo, foram utilizados 30 dentes humanos, todos igualmente preparados. No momento da cimentação dos pinos, as soluções irrigadoras foram: solução de soro fisiológico, hipoclorito de sódio 2,5% e solução de clorexidina 2%; e o cimento resinoso utilizado foi de cura dual. Após a cimentação, os espécimes foram seccionados, obtendo-se 2 fatias de aproximadamente 2 mm cada, suas faces cervicais foram marcadas, e então, submetidas ao teste de push-out. Foram realizados os testes ANOVA e Tukey, com nível de significância de 5 %, para a análise do ensaio mecânico e realizada análise qualitativa do tipo de falha ocorrida. Pôde-se observar que o grupo irrigado com hipoclorito de sódio 2,5% apresentou menor valor da média de resistência adesiva (3,870 ± 3,799 MPa), comparado com o grupo da clorexidina 2% (4,215 ± 2,098 MPa) e com o grupo do soro (4,510 ± 1,186 MPa). Já em relação aos terços, a região média foi a que apresentou maior valor da média de resistência adesiva (4,803 ± 3,14 MPa) quando comparado com a região cervical (3,593 ± 1,717 MPa), porém não houve diferença estatística significante, nem entre as regiões e nem entre as soluções irrigadoras. A maioria das falhas ocorridas foram do tipo adesiva 70%, enquanto que 23,33% foram fraturas coesivas, e 6,66% foram do tipo mistas. Assim, é possível concluir que os...
Currently, the fiberglass posts have emerged as an alternative to restore endodontically treated teeth. However, the loss of retention of the pin is a major cause of failure. Therefore, the aim of this study was to evaluate and compare the bond strength of transparent fiberglass posts, using a dual cure cement, varying the irrigating solution used during the preparation of the root canals through the push-out test and then a qualitative analysis of types of adhesion failures was made by reading into a stereomicroscope. For the study, 30 human teeth were used, all equally prepared. At the time of cementation of the posts, the irrigating solutions were: normal saline solution, sodium hypochlorite 2.5%, and 2% chlorhexidine solution, and the resin cement used was dual-curing. After cementation, specimens were sectioned, yielding two slices of about 2 mm each, their cervical faces were marked, and then subjected to push-out test, the data obtained were analyzed by descriptive and inferential statistics. The tests performed were ANOVA and Tukey, with a significance level of 5% for the analysis of mechanical test, and the type of failure occurred was qualitatively evaluated. It could be observed that the group irrigated with sodium hypochlorite 2.5% showed the lowest mean bond strength (3.870 ± 3.799 MPa), compared with 2% chlorhexidine group (4.215 ± 2.098 MPa) and the normal saline solution group (4.510 ± 1.186 MPa). In relation to the thirds, the middle region showed the highest value of bond strength average (4.803 ± 3.14 MPa) compared with the cervical (3.593 ± 1.717 MPa), but differences were not statistically significant, nor between regions nor between irrigating solutions. Most failures were adhesive type 70%, while 23.33% were cohesive fractures, and 6.66% were mixed type. Thus, we conclude that the irrigation protocols evaluated in this study did not exert effects on the bond ... (Complete abstract click electronic access below)
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26

Lima, Luiz Rafael Calixto. "Influência do sistema de cimentação adesiva e da fonte de luz fotoativadora na resistência à extrusão de pinos de fibra de vidro /." Araraquara : [s.n.], 2009. http://hdl.handle.net/11449/89623.

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Resumo: A retenção de pinos pré-fabricados de fibra de vidro, utilizados na restauração de dentes com tratamento endodôntico, é baseada na sua união às superfícies das paredes do canal radicular, por meio dos agentes de fixação resinosos. O tipo de pino utilizado, assim como a fonte de luz fotoativadora do cimento, também pode influenciar nessa retenção, principalmente nas regiões mais críticas do canal, como o terço apical, onde há uma grande dificuldade de acesso dessa luz ativadora. Assim, o propósito deste trabalho foi avaliar comparativamente a influência de diferentes sistemas de cimentação (químico convencional; dual convencional, químico com adesivo auto-condicionante, dual com adesivo auto-condicionante e cimento dual auto-adesivo), na resistência à extrusão (push-out) de pinos de fibra de vidro, nos diferentes terços do canal (cervical, médio, aplical). Foi avaliada também a influência do tipo de fonte de luz fotoativadora do cimento: luz halógena (Optilux 501) e LED (Ultraled). O tipo de falha foi avaliado através de microscopia. Foram utilizadas 240 unidades experimentais, em forma de discos, com aproximadamente 1 mm de espessura, retirados de 80 raízes bovinas, restauradas com retentores intraradiculares. Foi utilizada uma máquina de ensaios universais, MTS 810 Material Test System, à velocidade de 0,5 mm/min-1, com célula de carga de 50 Kg, para avaliação da resistência push-out nos diferentes terços de cada corpo-de-prova. Os valores de resistência em kgf, foram convertidos para MPa e analisados por meio de Análise de Variância e teste de Tukey, com nível de significância de 5%. Os resultados mostraram baixos valores de retenção para os grupos com os cimentos autoadesivos,independente da fonte de luz utilizada. Os cimentos de condicionamento ácido total e os de adesivos auto-condicionantes parecem ser opções viáveis no processo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The retention of prefabricated glass fiber posts, used for the restoration of endodontically-treated teeth, is based on adhesive systems and resin luting cements. The type of posts used, as well as the type of activation of the cement can also influence this retention, mainly in more critical areas of the radicular dentin, such as the apical root segments, where there is a great difficult access of the light curing units. Thus, the purpose of this study was to evaluate the influence of different resin cements (Chemical-cure total-etch; dual-cure total-etch; chemicalcure and self-etch bonding system, dual-cured and self-etch bonding system; and dual-cure self-adhesive cement) on the bond strength (push-out) of glass fiber posts on the different thirds of the root (cervical, middle and apical). The influence of the light curing unit was evaluated by halogen LCU (Optilux 501) and by LED LCU (LEC II 470) use. The failure mode was evaluated by stereoscopic microscope. Disks of the samples (n=240) were used, with approximately 1 mm of thickness of 80 bovine roots restored with glass fiber posts. A universal testing machine (MTS 810 Material Test System) was used with a 1 mm diameter steel rod at cross-head speed of 0,5 mm/min until post extrusion, with load cell of 50 kg, for evaluation of the push-out strength in different thirds of each sample. The pushout strength values in kgf were converted to MPa and analyzed through Analysis of Variance and Tukey's test, with significant level of 5%. The results of the present study showed that the self-adhesive cements group resulted in low retention values, in every light source utilized. The total-etch cements and the self-etch bonding systems seem to be a viable alternative in the glass fiber posts cementation process, with either halogen light or LEDs.
Orientador: Marcelo Ferrarezi de Andrade
Coorientador: Alessandra Nara de Souza Rastelli
Banca: José Roberto Cury Saad
Banca: Edson Alves de Campos
Mestre
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Pineda, Ana Raquel Pineda. "Resistência de incisivos centrais superiores irrigados com EDTA e portadores de retentores intra-radicular." Programa de Pós- Graduação em Odontologia da UFBA, 2006. http://www.repositorio.ufba.br/ri/handle/ri/10519.

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Foi realizado um estudo in vitro para avaliar a resistência de dentes anteriores tratados endodonticamente, que foram irrigados com EDTA 17%, pH 7,0 durante 1 e 3 minutos e portadores de retentor intra-radicular, fundido em liga de Níquel-Cromo. Foram utilizados 30 incisivos centrais superiores de dimensões semelhantes. As raízes foram instrumentadas pela técnica escalonada e a irrigação final foi feita com a solução em estudo. Posteriormente os retentores foram cimentados com fosfato de zinco e os corpos de prova levados à máquina de ensaio Instrom 1122, com velocidade de 0,5 mm/min, para ser submetidos a teste de compressão. Os resultados foram avaliados, usando-se a Análise de Variância (ANOVA), o Teste de Tukey, o teste t de Student e o teste de Kolmogorov-Smirnov, mostrando que houve diferença, estatisticamente significante (p= 0.014), entre o grupo irrigado com EDTA 1 min e o grupo irrigado com detergente.
Salvador
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28

Supriyanto. "Micropropagation de pinus nigra et pinus sylvestriS : Application à leurs hybrides interspécifiques." Nancy 1, 1989. http://www.theses.fr/1989NAN10253.

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(. . . ) La production massive de bourgeons axillaires et adventifs a été obtenue avec des apex de semis de 40 à 110 jours par P. Nigra et P. Sylvestris. Pour le développement de bourgeons axillaires et l'induction des bourgeons adventifs, le milieu minéral de Murashige et Skoog (MS) et le milieu organique de Bourgin et Nitsch (BN), tous les deux dilués deux fois (MSBN/2), ont été employés avec des rapports cytokinine : auxine variés. Le bourgeonnement total (axillaire et adventif) chez P. Nigra est plus élevé que chez P. Sylvestris, quelles que soient les conditions de culture. (. . . )
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29

Agostini, Estelamaris. "Da araucária ao pinus." Florianópolis, SC, 2001. http://repositorio.ufsc.br/xmlui/handle/123456789/79785.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas. Programa de Pós-Graduação em Geografia
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Através de estudo evolutivo do uso do solo no Distrito de Santa Terezinha do Salto, no Município de Lages em Santa Catarina procurou-se compreender as relações que se estabelecem no âmbito social, econômico e político do mesmo, tendo como principal objetivo analisar o quanto a paisagem contribui para o desenvolvimento regional. A premissa é a valorização do ambiente natural, frente a questão ambiental. Esta análise possibilitou evidenciar algumas correlações entre homem e natureza, na busca do que se denomina sustentabilidade.
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30

Lopes, Helena de Fátima Silva. "Microbiome of Pinus pinaster." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16427.

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Mestrado em Microbiologia
Pinus pinaster has a great environmental, historical and economical importance to Portugal. It represents the third place in occupation in forestry area. However, it has been losing area due to the modifications on land use, fires and diseases such as the pine wilt disease (PWD). Native from the North America the PWD has been spreading worldwide, it has spread through Asia and more recently was identified in Europe being detected in Portugal in 1999, representing a major threat to forests. Recently, the importance of the bacteria community to the PWD has been accessed and few studies address the microbiome of P. pinaster. Most of the existing studies uses culture-dependent techniques. This work aimed to reveal the bacterial community of healthy P. pinaster trees using culture-independent techniques. To observe the bacterial communities of healthy P. pinaster, stem samples from trees aged between 20 and 30 years were collected from 4 Portuguese locations: Comporta, Góis, Madeira Island and Vouzela. The trunks were cut into disks and the sawdust of the center of these disks were used to extract DNA. Samples were tested for the presence of the PWD nematode and all were negative. DGGE analysis was performed to compare the bacterial community of different samples and pyrosequencing was used to identify the community. After analyzing the DGGE profiles, a sample was cloned and sequenced, and the results showed that the most common and intense bands belonged to chloroplast genetic material. Pyrosequencing results had a great amount of reads belonging to chloroplast and they were eliminated from the study. With the pyrosequencing, six plyla were detected: Proteobacteria, Acidobacteria, Firmicutes, Bacteriodetes, Armatimonadetes and Actinobacteria. Proteobacteria was the most common, and from this plylum, Gammaproteobacteria was the most abundant class. Samples grouped by location and the location community differ significantly, only two OTUs were shared by all locations. Despite the low read number the bacterial community was characterized, and this information can be used for future studies.
Pinus pinaster possui uma grande importância ambiental, histórica e económica em Portugal, conquistando o terceiro lugar em ocupação florestal. Entretanto sua área está a diminuir devido a modificações na utilização dos terrenos, fogos e doenças como a da murchidão do pinheiro (DMP). Nativa da América do Norte, a DMP vem se espalhando em uma escala global, já está presente na Ásia e mais recentemente na Europa, sendo detectada em 1999 em Portugal, representando assim uma ameaça a florestas do mundo inteiro. Existem evidências que apontam para a importância da comunidade bacteriana no desenvolvimento da DMP e poucos estudos abordam o microbioma do P. pinaster, com a maioria utilizando metodologias baseadas em cultivo. Este trabalho tem como objetivo revelar a comunidade bacteriana de árvores de P. pinaster saudáveis utilizando técnicas independentes de cultivo. Para observar a comunidade bacteriana do P. Pinaster saudável, árvores entre 20 e 30 anos de idade foram recolhida de 4 localidades portuguesas: Comporta, Góis, Ilha da Madeira e Vouzela. O tronco dessas árvores foi cortado em discos e o serrim do centro desses discos foi utilizado para extração de DNA. Todas as amostras foram testadas para a presença do nemátodo sendo que este estava ausente em todas as amostras. Foi feito DGGE com o objectivo de comparar a comunidade bacteriana de diferentes amostras, e esta foi identificada utilizando-se pirosequenciação. Tendo em conta os perfis de DGGE, foi feita a clonagem e sequenciação de uma das amostras, e verificou-se que as bandas mais intensas, e presentes em todas as amostras, eram material genético proveniente de cloroplastos. Os resultados de pirosequenciação revelaram uma grande quantidade de reads proveniente de cloroplastos que foram eliminadas do estudo. A análise dos resultados da pirosequenciação permitiu identificar seis filos: Proteobacteria, Acidobacteria, Firmicutes, Bacteriodetes, Armatimonadetes e Actinobacteria. Proteobacteria foi o filo mais comum e dele Gammaproteobacteria foi a classe mais abundante. As amostras se agruparam de acordo com o local de origem e as comunidades dos locais se diferenciavam significativamente. Apenas duas OTUs eram compartilhadas por todos os locais. Apesar do baixo número de reads, a estrutura da comunidade bacteriana foi caracterizada e essa informação pode ser agora utilizada em futuros estudos.
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31

Chiron, Hélène. "Effets de l'ozone et/ou d'un champignon pathogène dans les aiguilles et le phloème de pins sylvestre (Pinus sylvestris L. ) : étude moléculaire du métabolisme des stilbènes." Nancy 1, 2000. http://www.theses.fr/2000NAN10047.

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La présente étude décrit d'une part le clonage moléculaire et l'expression fonctionnelle du gène pinosylvine méthyltransférase (PMT), et d'autre part l'induction par l'ozone des gènes stilbène synthase (STS) et PMT, responsables de la synthèse des stilbènes, chez des pins sylvestres (Pinus sylvestris L. ) âgés de 7 ans, soumis ou non à des inoculations sériles ou fongiques (Leptographium wingfieldii). [. . . ]
The present study describes first the molecular cloning and the functional expression of the pinosylvin O-methyltransferase (PMT) gene, and then the dose-dependent ozone induction of stilbene synthase (STS) and PMT genes responsible of stilbene biosynthesis in needles and sapwood of 7-year-old Scots pine trees prior to sterile and fungal inoculations (Leptographium wingfieldii)
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32

Monteiro, Pedro Emanuel de Oliveira. "Deciphering Pinus-Fusarium circinatum interaction in Pinus species with different degrees of susceptibility." Master's thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22746.

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Mestrado em Bioquímica
A doença do cancro resinoso do pinheiro é causada por um agente patogénico - Fusarium circinatum, que afeta o género Pinus e também a espécie Pseudotsuga menziesii. Desde a sua descoberta em 1946, nos Estados Unidos da América, que a doença se tem dissipado pelo mundo provocando elevadas perdas económicas. Os sintomas característicos da doença são a descoloração, murchidão e queda das agulhas, o tombamento do ápice e a formação de cancros com exsudação visível de resina. Apesar das medidas de controlo aplicadas nos viveiros e plantações, ainda não existe um método eficaz para o controlo da doença sendo a seleção de material vegetal mais tolerante a ferramenta mais recomendada. Para tal, é crucial entender o mecanismo de infeção deste agente patogénico. Neste trabalho foram utilizadas três espécies de pinheiro, com diferentes graus de suscetibilidade - P. radiata, P. pinaster e P. pinea. Depois de 30 dias de aclimatização em câmara climática as plantas foram artificialmente inoculadas no caule com uma suspensão de esporos de F. circinatum. Para cada espécie foi implementado um grupo controlo (não inoculado). A amostragem foi realizada quando 50% dos indivíduos de um tratamento de cada espécie mostrou os sintomas característicos da doença – descoloração das agulhas, tombamento do ápice - tendo-se avaliado os seguintes parâmetros fisiológicos e bioquímicos: sobrevivência da planta, necrose relativa, trocas gasosas, relações hídricas, libertação de eletrólitos, pigmentos, prolina, açúcares solúveis totais e amido. Foram ainda realizados cortes histológicos para comparação anatómica do caule entre plantas controlo das três espécies. Após a infeção com F. circinatum, P. radiata foi a primeira espécie a mostrar sintomas – descoloração das acículas e tombamento do ápice, após 10 dias após inoculação, seguindo-se P. pinaster (17 dias) e por fim P. pinea (64 dias), onde apenas foi possível observar maior exsudação de resina e ramos laterais secos perto do ponto de inoculação. A inoculação com F. circinatum causou o aumento dos valores de necrose relativa em P. radiata e P. pinaster acompanhado com um aumento dos valores de libertação de eletrólitos. Em P. pinea não foram observadas estas alterações. Foi possível observar a resposta da planta a F. circinatum no que se refere ao seu impacto nas relações hídricas em P. radiata e P. pinaster através da diminuição do potencial hídrico e uma diminuição significativa no conteúdo relativo em água nesta ultima espécie, sem alterações em P. pinea. A prolina também teve um aumento significativo em P. pinaster. Nas espécies mais suscetíveis, P. radiata e P. pinaster, as trocas gasosas foram severamente afetadas ocorrendo um decréscimo na taxa de assimilação de CO2, condutância estomática, transpiração e eficiência no uso de água, inversamente à concentração interna de CO2 que registou um aumento. Observou-se um aumento das antocianinas, com maior incidência em P. pinaster e P. pinea. As diferenças a nível anatómico entre as três espécies estudadas, principalmente na espessura do córtex e no número de canais resiníferos, podem ser parte da explicação da tolerância encontrada em P. pinea. Os resultados apontam para uma maior plasticidade no ajuste osmótico em P. pinaster comparativamente a P. radiata que suporta o atraso verificado no aparecimento de sintomas apesar da maior proporção de necrose relativa observada. Com este estudo foi possível confirmar que a infeção com F. circinatum leva a uma resposta diferencial nas três espécies em estudo não só em termos temporais como aparentemente nos mecanismos de resposta que lhe estão associados.
Pitch canker disease (PCD) is caused by a pathogen – Fusarium circinatum, which affects Pinus genus and also the species Pseudotsuga menziesii. Since its first report in 1946, in the United States of America, the disease has spread worldwide provoking severe economic losses. The characteristic symptoms of the disease are the wilting and discoloration of the needles, that end up falling down, the tip dieback of the branches, and the formation or large cankers with visible resin exudation. Despite the control measures applied in nurseries and plantations, there is still no effective method for disease control, being the selection of tolerant plant material the most recommended tool. To do this, it is crucial to understand the pathogen infection mechanism. In this work three pine species with different degrees of susceptibility - P. radiata, P. pinaster and P. pinea, were used. After 30 days of an acclimatization period in a climatic chamber, plants were artificially inoculated in stems with a spore suspension of F. circinatum. A control group (not inoculated) was also implemented. Sampling was performed when 50% of the individuals of a treatment within each species showed the characteristic symptoms of the disease - needles discolouration, tip dieback - and the following physiological and biochemical parameters were evaluated: plant survival, relative necrosis, leaf-gas exchanges, water relations, electrolyte release, pigments, proline, total soluble sugars and starch. Histological sections were also performed between for comparison of control plants between the three species. After infection with F. circinatum, P. radiata was the first species to show symptoms, after 10 days-post-inoculation, followed by P. pinaster (17 days) and finally P. pinea (64 days), where it was only possible to observe a higher resin exudation and discoloured lateral branches near the inoculation point. The inoculation with F. circinatum caused the increase of the relative necrosis values in P. radiata and P. pinaster, where it was also possible to observe an increase on the values of electrolyte leakage. These changes were not observed in P. pinea. It was possible to observe the plants’ response to F. circinatum infection regarding its impact on the plant-water relations in P. radiata and P. pinaster through a decreased water potential and a significant decrease in relative water content in this last species, without changes in P. pinea. Proline also had a significant increase in P. pinaster. In the most susceptible species, P. radiata and P. pinaster, leaf-gas exchanges parameters were severely affected, with a decrease of net CO2 assimilation rate, stomatal conductance, transpiration and water-use efficiency, inversely to internal CO2 concentration, which increased. An increase in anthocyanins was observed, with a higher incidence in P. pinaster and P. pinea. The anatomical differences between the three species studied, mainly in the thickness of the cortex and in the number of resin ducts, may be part of the explanation of the tolerance found in P. pinea. The results point to a greater plasticity in the osmotic adjustment in P. pinaster compared to P. radiata that supports the delay observed in the symptoms appearance despite the higher relative necrosis observed. With this study it was possible to confirm that the infection with F. circinatum leads to a differential response in the three species used, not only temporally related but also in the response mechanisms associated.
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33

Asary, Melanie. "An investigation into the poor emergence of Pinus elliottii and Pinus taeda seeds." Thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/26349.

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34

Kadri, Nabil. "Graines de Pinus SP : caractérisation physico-chimique et activité anticancéreuse." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20143/document.

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Les graines de pin (Pinus halepensis Mill., Pinus pinea L., Pinus pinaster et Pinus canariensis) sont les quatre espèces les plus disponibles dans le bassin méditerranéen. Elles sont très utilisées par les populations Nord-africaines en médecine traditionnelle et en gastronomie où elles agrémentent les plats traditionnels (salades, riz, poissons …etc), car elles sont bien connues pour leur excellent goût salé. Cependant, la composition biochimique, les valeurs nutritionnelles, et les mécanismes d'actions cellulaires et moléculaires via lesquels ces graines exercent leurs effets thérapeutiques restent mal élucidés. Le but de notre travail est d'étudier les propriétés physico-chimiques des graines de quatre espèces de pin et la valeur nutritionnelle et pharmaceutique des fractions lipidiques des graines de Pinus halepensis Mill., en utilisant différentes techniques de séparation et d'analyse telles que (DRX, IRTF, CC, LC/MS, GC, GC/MS et RMN) et en examinant la voie principale impliquée dans le développement du cancer qui est l'angiogenèse via des essais biologiques in vitro sur la prolifération et la migration des cellules endothéliales sur Matrigel et in vivo sur une membrane chorioallantoïdienne (CAM) des œufs de poulet ainsi que leurs toxicités sur des cultures cellulaires (Myélome humain HL60, Adénocarcinome du coulon, humain HCT15, Cellules épithéliales A549 et cellules de mélanomes B16F1). Les résultats de la caractérisation physico-chimiques montrent que les quatre graines sont très riches en métabolites primaires (sucres, protéines, protéines de réserve) et secondaires (Phénols totaux et flavonoïdes) comme elles présentent une importante concentration en oligo-éléments (phosphore, potassium, magnésium, Zinc, fer, cuivre et manganèse). Leurs huiles essentielles sont riches en limonène. Les principaux acides gras insaturés pour les quatre espèces sont l'acide linoléique et l'acide oléique. Les propriétés chimiques et physiques de leurs huiles fixes sont dans la norme de qualité agroalimentaire. Les graines de Pinus halepensis Mill. sont les plus riches en lipides totaux qui atteignent un taux de 36% diversifiés chimiquement avec des lipides apolaires (Lipides neutres) et polaires (Quatre classes de glycolipides et six classes de phospholipides). Ces résultats sont de bons indicateurs de la qualité nutritionnelle des graines de pins et impliquent que les lipides neutres, les glycolipides et les phospholipides des graines de Pinus halepensis Mill. dépourvus de toxicité aux concentrations de 1, 10, 25, 50, 100 et 200µg/ml et ayant une activité cytotoxique à 500 et 1000µg/ml et anti-angiogénique in vitro à des concentrations de 100 et 500µg/ml et in vivo à des concentrations de 1mg /ml et 10 mg/ml peuvent être utilisés dans la prévention des maladies liées à l'angiogenèse et à la lutte contre le cancer
The pine (Pinus halepensis Mill., Pinus pinea L., Pinus pinaster and Pinus canariensis) seeds are the four most available species in the Mediterranean basin. They are widely used by North African populations in traditional medicine and gastronomy where they adorn the traditional dishes (salads, rice, fish ... etc) because they are well known for their excellent taste salty. However, the biochemical composition, nutritional value, and the cellular and molecular mechanisms of action through which these seeds exert their therapeutic effects remain poorly understood. The aim of our study was to investigate the physicochemical properties of pine seed species and nutritional and pharmaceutical value of lipid fractions of Pinus halepensis Mill. Seeds using different separation and analysis techniques such as (XRD, FTIR, CC, LC/MS, GC, GC/MS and NMR) and examining the main pathway involved in the development of cancer which is angiogenesis through biological tests in vitro on the proliferation and migration of endothelial cells on Matrigel and in vivo on a chorioallantoic membrane (CAM) of chicken eggs, thus that their toxicity on healthy cell cultures (human myeloma HL60, Adenocarcinoma of human coulon, HCT15, human epithelial cells, A549 and cells melanoma, B16F1). The results of the physico-chemical characterization showed that four seeds are rich in primary metabolites (sugars, proteins, protein reserves) and secondary (total phenolic and flavonoids) as they have a high concentration of trace elements (phosphorus, potassium, magnesium, zinc, iron, copper and manganese). Their essential oils are rich in limonene. The main unsaturated fatty acids of all species are linoleic acid and oleic acid. The chemical and physical properties of their fixed oils are the in standard food quality. Pinus halepensis Mill. seeds are the richest in total lipids which achieved a rate of 36% chemically diverse with non polar lipids (neutral lipids) and polar lipids (Four classes of glycolipids and six classes of phospholipids). These results are good indicators of the nutritional quality of pine seeds and imply that the neutral lipids, glycolipids and phospholipids of Pinus halepensis Mill. seeds devoid of toxicity at the concentrations of 1, 10, 25, 50, 100 and 200µg/ml and having cytotoxic activity at 500 and 1000µg/ml and anti-angiogenic effect in vitro at the concentrations of 100 and 500 µM and in vivo at the concentrations of 1 mg/ml and 10 mg/ml may be useful in prevention of angiogenesis-related and the fight against cancer diseases
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35

Aroni, Antônio Sérgio [UNESP]. "Avaliação da biomassa e qualidade da madeira do híbrido Pinus tecunumannii x Pinus caribaea var.hondurensis pela técnica de atenuação da radiação gama do 'INTPOT. 241 Am'." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/101947.

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Os principais objetivos são: a) Estudar as variações das densidades da madeira no sentido radial e longitudinal, utilizando a técnica de Atenuação da Radiação Gama do Amerício-241 e a técnica de Imersão; b) Avaliar a densidade média ponderada por árvore e por tratamento e, para isso, utilizará as espécies Seminal de Pinus caribaea var.hondurensise espécie híbrida de Pinus caribaea var.hondurensis x Pinus tecunumannii; c) Avaliar os índices de produtividade pelos Incrementos Médios Anuais de Volume (IMAV), Incrementos Médios Anuais de Massa (IMAM) e Incrementos Médios Anuais de Energia (IMAE) de cada tratamento, correlacionando-os com seus respectivos valores de densidade; d) Determinar o poder calorífico superior de cada tratamento pelo método da Bomba calorimétrica; e) Comparar os métodos Atenuação da radiação Gama do Amerício-241 e o de Imersão. Para o estudo foram selecionadas 45 árvores da empresa DURATEX S/A., na região de Agudos-SP., entre as espécies Seminal Pinus caribaea var.hondurensis e ahíbrida Pinus caribaea var.hondurensis x Pinus tecunumannii. Foram selecionados cinco tratamentos do híbrido de Pinus caribaea var.hondurensis x Pinus tecunumannii que mais se destacaram dentre os 12 híbridos existentes no povoamento, sendo denominados como 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' e um tratatamento de material Seminal do Pinus caribaea var.hondurensis, sendo denominado como S, espécie tropical de gênero Pinus proveniente de um ensaio vizinho equiâneo submetido às mesmas condições edafo-climáticas e submetido aos mesmo tratos culturais na implantação. A técnica de atenuação permite observar esses detalhes, o que não poderia ser feito com as técnicas tradicionais. Algumas árvores tiveram um comportamento mais uniforme para a densidade, demonstrando uma menor sensibilidade aos fatores climáticos...
The main objectives are: a) To study wood desity variations inthe radial and longidutinal directions, using the Americium-241 Gamma Radiation Attenuation technique and the immersion technique; b) To evaluate the average density mesaured per tree and per treatment and, for this, the Seminal species of Pinus caribaea var.hondurensis and the hybrid species of Pinus caribaea var.hondurensis x Pinus tecunumannii will be used; c) To evaluate the yield rates based on the Annual Average Volume Increments (AAVI), the Annual Average Mass Increments (AAMI) and the Annual Average Energy Increment (AAEI) of each treatment, correlating them to their respective density values; d) To determine the superior calorific power of each treatment by means of the calorimetric Bomb; e) To compare the Americium-241 Gamma Radiation Attenuation method and the Immersion method. For such study, 54 trees from the company DURATEX S/A were selected, in the region of Agudos-SP, among Seminal species of Pinus caribaea var.hondurensis and the hybird Pinus caribaea var.hondurensis x Pinus tecunumannii. Five treatments of the hybrid of Pinus caribaea var.hondurensis x Pinus tecunumannii were selected, which were the most important among the 12 ones which existed in the population, being named as 'H IND. 1', 'H IND. 2', 'H IND. 3', 'H IND. 4', 'H IND. 5' and a Seminal material treatment of Pinus caribaea var.hondurensis, beinh named as S, tropical species of the family Pinus coming from an equineous neighbor study which underwent the same edaphic-climatic conditions and which underwent the same cultural traits in their implantation. The attenuation technique allows the observation of such details, which could not be made with traditional techniques. Some trees had a more uniform behavior concerning density, demonstrating a lower sensitivity to climatic factors. The used methods for the basic wood density collection... (Complete abstract click electronic access below)
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36

Santiago, Luiz Fernando Frezzatti [UNESP]. "Carcterização da influência da velocidade de corte, pressão e granulometria de lixa no lixamento plano do Pinus elliottii." Universidade Estadual Paulista (UNESP), 2011. http://hdl.handle.net/11449/94399.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
No presente trabalho é válido o processo de lixamento da matéria de Pinus elliottii. O objetivo principal do estudo foi entender a influência e interação dos fatores de entrada (granulometria de lixa, velocidade de corte e pressão) sobre as variáveis de saída (taxa de remoção de material, temperatura, rugosidade, potência consumida, força de lixamento, emissão acústica e integridade superficial no processo de lixamento plano da madeira Pinus elliottii, processado paralelo às fibras. O lixamento foi realizado em uma lixadeira plana com sistema de monitoramento e aquisição de dados. Utilizou-se um delineamento de blocos completamente aleatorizados para a realização do experimento. Foram ulitizados quatro tipos de granulometrais de lixa, três velocidades de corte e três pressões, com seis repetições para cada combinação totalizando 216 tratamentos. Os resultados foram analizados através de uma análise de variância (ANOVA) com nével de significância de 5%. para taxa de remoção de material foi observado que a granulometria de lixa, pressão e velocidade influenciaram significativamente. Com relação à temperatura, somente a granulometria de lixa teve uma influência significativa no aquecimento do sistema. Para o acabamento superficial, apenas a granulometria de lixa influenciou significativamente na rugosidade. O consumo de potência foi influenciado pela velocidade de corte e pressão. Para a força de lixamento, a granulometria de lixa e a pressão influenciaram significativamente. Na emissão acústica somente a granulometri de lixa influenciou significativamente no sinal captado. Para a análise de imagens foram observados diferenças no acabamento conforme se aumenta a granulometria da liza. Não foi observada nenhuma interação significativa entre os fatores velocidade de corte e pressão para todas as variáveis de saída estudadas
This study refers to about sanding process of Pinus elliottii wood following the direction of grain. The first aim of this work is trying to undersand the influence of the following factors: belt speed, pressure and grit size on the output parameters of material remove rate, temperature, roughness, image, analysis, cutting force, power consumption and acoustic emisson. It was used a sanding belt with a data acquisition system to record the output variables. For the experiment it was used a randomized block design. The level of factors consider in the experiment it were four size of grit, three levels of pressure and three levels of belt speed. The experiment total treatments of belt speed, pressure and grit size (3 x 3 x 4=36 ) was run with six replicates for a total 216 expeiments. The results of output parameters were analyzed through the analysis of variance (ANOVA) with level of significance 5%. All the factors were significant to material remove rate. Only grit sizes were significant to the differnt levels temperature. The same behavior it was observed to the roughness where only grits size were significant. Differently the power consumption was not significant to the grits size but it was significant to the levels of pressure and belt speed. It was observed that grits sizes and pressure caused significant influence on cutting force. Only grits size significant to the acoustic emission. It was observe on analysis of image that the coarse grit produces a rougher surface than the smooth grit and anatomical elements showed up more when smooth grit was used. It could not found any interaction between the factors to all outputs parameters
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37

Cardoso, Denise Jeton. "Viabilidade técnica e econômica da poda em plantações de Pinus Taeda e Pinus Elliottii." reponame:Repositório Institucional da UFPR, 2013. http://hdl.handle.net/1884/24234.

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Brazil first began concerning about producing pine clearwood 30 years ago, even though it has been quite a common activity in other countries for several years. The wood originated from the first pruned pine plantations began to be harvested in recent years. However, the procedures used in the pruning operation vary from region to region, as well as the thinning regime and quality of the site, which directly affect the growth of the trees and the amount of knot-free wood produced at the end of the rotation. The expected price for this product is equal to or greater than 100% of the wood value for the same grade, without pruning. However, due to the increasing production of composition boards and other changes taking place in the market, clearwood prices have been decreasing, coming close to the prices of unpruned wood. One of the objectives of this study was to quantify the clearwood volumes effectively and potentially generated from pruned logs. Another objective was to establish the minimum price to be charged for the pruned wood so that the same economic result from an unpruned stand could be achieved, considering the costs of pruning and yield in commercial volume in each situation. Yet, the maximum price to be asked for was calculated in order to make it an advantage to buy pruned logs rather than buying clearwood veneer in the market. The cost of pruning only the first log and pruning the first two logs of each tree was considered. The data were taken from eight stands located in the regions of Jaguariaíva, Sengés and Ibaiti, all in Paraná State, and the region of Itapeva, in São Paulo State. The ages of the plantations range between 18 and 24 years old, seven stands being of Pinus taeda and one of Pinus elliottii. The log batches were processed in veneer companies located in Sengés and Ibaiti. The log processing was efficient, for it was possible to measure the diameter of the knotty core as the first knot was shown. The results show that on average 52.9 % of the volume of the batch from the first logs corresponds to the volume of potentially clearwood against 50.1 %, obtained in the batches containing second logs. However, 10.8 % of the volume of these logs was turned into clearwood veneer, whereas in the batches from unpruned stands, this percentage did not exceed 2.3 %. It was observed that the second log has a better shape than the first, both in pruned and unpruned batches, although the volume of the second log is smaller. The pruned trees have a better shape than the unpruned trees and they achieved, on average, 6.5 % more volume than the latter, for the same dbh (diameter at breast height) and height. Regarding the price, the pruned logs must have, in relation to the value of the same grade unpruned, a minimal additional of 53.9 %, so as the same economic result from an unpruned stand and a maximum additional of 77 % can be achieved, so that the buyer might prefer to purchase these logs instead of purchasing the veneers. It is recommended that pruning be performed only on the first log, preferably in very productive sites, due to the uncertainty about the demand for clearwood. Performing pruning on the second log is considered important to make up for the small amount of clearwood in stands of low and medium productivity.
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Silva, Luciana Mendonça da. "Resistência da união da cimentação adesiva de pinos de fibra de vidro frente ao teste de remoção por extrusão." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/25/25131/tde-29052009-100558/.

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Este trabalho avaliou a resistência de união de pinos de fibra de vidro cimentados à dentina com o uso de um cimento resinoso convencional e um auto-adesivo. Trinta dentes bovinos unirradiculares tiveram as raízes 17mm a partir dos ápices. As raizes foram tratadas endodonticamente e divididas aleatoriamente em 3 grupos (n=10): G1- cimento resinoso convencional RelyX ARC + ScotchBond Multi Uso Plus (SBMP) fotoativado + pino de fibra de vidro; G2 RelyX ARC + SBMP quimicamente ativado + pino de fibra de vidro; G3 cimento resinoso auto-adesivo RelyX U100 + pino de fibra de vidro. Após a cimentação dos pinos, os espécimes foram armazenados por 24 horas em água destilada, à 37oC. As raízes foram cortadas sob irrigação constante para obter de 6 a 9 fatias de 1mm de espessura. O teste de resistência à extrusão foi realizado para medir a resistência adesiva nas fatias da região cervical, média e apical, a uma velocidade de 0,5mm/min. Todos os espécimes foram observados em microscópio ótico de luz para avaliar os tipos de falhas. Os valores foram submetidos à análise de variância a dois critérios (ANOVA) e teste de Tukey (p0,05). As médias gerais dos grupos 1, 2 e 3, respectivamente, (MPa) foram de 4,87 (±3,65); 5,89(±3,72); e 8,50(±4,52). Os valores de resistência adesiva regional nos terços cervical, médio e radicular, respectivamente, foram: G1- 5,26(±3,44); 5,11(±3,33); 5,01(±3,17); G2- 7,45(±3,82); 5,88(±2,50); 4,91(±2,74); G3- 10,11(±3,11); 9,12(±3,70); 4,99(±3,28). Os maiores valores de resistência adesiva foram encontrados com o cimento auto-adesivo. Ao avaliar os terços separadamente, os grupos 2 e 3 obtiveram comportamento semelhante nos terços cervical e médio. No terço apical, todos os grupos tiveram o mesmo comportamento. A resistência de união foi influenciada pelo tipo de cimento utilizado e região radicular, mas não foi alterada pela variação do modo de polimerização do sistema adesivo.
This work evaluated the bond strength of glass fiber posts to dentin using a conventional and a self-adhesive resin cement. Thirty bovine incisors had their roots sectioned 17mm from their apices, endodontically treated and assigned into 3 groups (n=10): group 1, conventional resin cement RelyX ARC + ScotchBond Multi Purpose Plus (SBMP) light activated + glass fiber post; Group 2, RelyX ARC+ SBMP chemically activated + glass fiber post; Group 3, self-adhesive resin cement RelyX U100 + glass fiber post. After luting, specimens were stored for 24 hours in distilled water at 37oC. Roots were sliced under water irrigation to obtain 1mm thick slices. Push-out test was performed on each slice with a universal testing machine with a crosshead speed of 0,5mm/min. All fractured specimens were observed using a light microscope to identify modes of failure. Values were submitted to two-way ANOVA and Tukeys test (p0,05). Mean values (MPa) and standard deviation for groups 1, 2 and 3 were, respectively: 4.87 (±3.65); 5.89(±3.72); e 8.50(±4.52). Regional bond strength values for the cervical, medium and apical were: G1- 5.26(±3.44); 5.11(±3.33); 5.01(±3.17); G2- 7.45(±3.82); 5.88(±2.50); 4.91(±2.74); G3- 10.11(±3.11); 9.12(±3.70); 4.99(±3.28). The highest bond strength values were obtained using the self-adhesive cement. Regional bond strengths were similar in the cervical and medium region in groups 2 and 3. All cements had the same performance on the apical region. Bond strength was influenced by the type of cement used and radicular region, but was not altered by the activation mode of the bonding system.
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39

Lima, Luiz Rafael Calixto [UNESP]. "Influência do sistema de cimentação adesiva e da fonte de luz fotoativadora na resistência à extrusão de pinos de fibra de vidro." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/89623.

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A retenção de pinos pré-fabricados de fibra de vidro, utilizados na restauração de dentes com tratamento endodôntico, é baseada na sua união às superfícies das paredes do canal radicular, por meio dos agentes de fixação resinosos. O tipo de pino utilizado, assim como a fonte de luz fotoativadora do cimento, também pode influenciar nessa retenção, principalmente nas regiões mais críticas do canal, como o terço apical, onde há uma grande dificuldade de acesso dessa luz ativadora. Assim, o propósito deste trabalho foi avaliar comparativamente a influência de diferentes sistemas de cimentação (químico convencional; dual convencional, químico com adesivo auto-condicionante, dual com adesivo auto-condicionante e cimento dual auto-adesivo), na resistência à extrusão (push-out) de pinos de fibra de vidro, nos diferentes terços do canal (cervical, médio, aplical). Foi avaliada também a influência do tipo de fonte de luz fotoativadora do cimento: luz halógena (Optilux 501) e LED (Ultraled). O tipo de falha foi avaliado através de microscopia. Foram utilizadas 240 unidades experimentais, em forma de discos, com aproximadamente 1 mm de espessura, retirados de 80 raízes bovinas, restauradas com retentores intraradiculares. Foi utilizada uma máquina de ensaios universais, MTS 810 Material Test System, à velocidade de 0,5 mm/min-1, com célula de carga de 50 Kg, para avaliação da resistência push-out nos diferentes terços de cada corpo-de-prova. Os valores de resistência em kgf, foram convertidos para MPa e analisados por meio de Análise de Variância e teste de Tukey, com nível de significância de 5%. Os resultados mostraram baixos valores de retenção para os grupos com os cimentos autoadesivos,independente da fonte de luz utilizada. Os cimentos de condicionamento ácido total e os de adesivos auto-condicionantes parecem ser opções viáveis no processo...
The retention of prefabricated glass fiber posts, used for the restoration of endodontically-treated teeth, is based on adhesive systems and resin luting cements. The type of posts used, as well as the type of activation of the cement can also influence this retention, mainly in more critical areas of the radicular dentin, such as the apical root segments, where there is a great difficult access of the light curing units. Thus, the purpose of this study was to evaluate the influence of different resin cements (Chemical-cure total-etch; dual-cure total-etch; chemicalcure and self-etch bonding system, dual-cured and self-etch bonding system; and dual-cure self-adhesive cement) on the bond strength (push-out) of glass fiber posts on the different thirds of the root (cervical, middle and apical). The influence of the light curing unit was evaluated by halogen LCU (Optilux 501) and by LED LCU (LEC II 470) use. The failure mode was evaluated by stereoscopic microscope. Disks of the samples (n=240) were used, with approximately 1 mm of thickness of 80 bovine roots restored with glass fiber posts. A universal testing machine (MTS 810 Material Test System) was used with a 1 mm diameter steel rod at cross-head speed of 0,5 mm/min until post extrusion, with load cell of 50 kg, for evaluation of the push-out strength in different thirds of each sample. The pushout strength values in kgf were converted to MPa and analyzed through Analysis of Variance and Tukey’s test, with significant level of 5%. The results of the present study showed that the self-adhesive cements group resulted in low retention values, in every light source utilized. The total-etch cements and the self-etch bonding systems seem to be a viable alternative in the glass fiber posts cementation process, with either halogen light or LEDs.
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40

Vetayasuporn, Sopit. "Genetic variation in Pinus kesiya." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301651.

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41

Collin, Niklas, Carl Ögren, and Martin Thyrestam. "Frekvensanalys av pinne-skiva maskin." Thesis, KTH, Maskinkonstruktion (Inst.), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-183038.

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Denna rapport utreder funktion och problematik med en pinne-skiva maskin som används på Institutionen för Maskinkonstruktion vid KTH. Denna maskin används för forskning kring nötning av bland annat bromsskivor och belägg. Maskinen har påvisat ett ojämnt beteende vid vissa driftsfall, något som utreds i denna rapport. Resultaten har inte verifierats av faktisk provning utan består enbart av modellexperiment. Vad som framgick av analysen är att problematiken förekommer vid frekvenser vida högre än maskinens egna varvtal utan är ett resultat av dess övertoner. Problematiken kan primärt identifieras kring 80 Hz. Konstruktionsförändringar för att minska problemen redovisas.
This report investigates function and problems with a pin-disc machine used at the KTH Department of Machine Design. This machine is used for research on the wear of brake discs and pads. The machine reveals an uneven behavior at certain operating conditions, which are investigated in this report. The results have not been verified by actual physical testing.What has emerged from the analysis are problems that occurs at frequencies much higher than the machine's speed but is a result of its harmonic behavior. The problem can be primarily identified around 80 Hz. Structural modifications to reduce the problems are also presented.
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42

Lara, Susana Favela. "Taxonomy of some Mexican Pines." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670355.

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43

Bastide, Brigitte. "Etude des conditions de régénération de trois pinacées (Pinus halepensis Mill., Pinus pinaster Aiton subsp. pinaster et Pinus pinea L.) en milieu dunaire littoral." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376116385.

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44

Sathyan, Pratheesh. "Identification of drought responsive genes in aleppo pine (Pinus halepensis) and loblolly pine (Pinus taeda.L)." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1528.

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Drought is a major constraint for attaining economic yield in tree crops. As an initial step to understand molecular response to water-deficit-stress in trees, gene expression in response to water stress was quantified using real-time RT-PCR. The specific objectives established for this to were I. to identify and characterize the genes induced by drought stress in Aleppo pine (Pinus halepensis) and II to identify and quantify the differentially expressed genes in different populations of Loblolly pine (Pinus taeda.L) due to water deficit (chapter III). Results of these studies may be used to identify candidate genes for future breeding programs against water-deficit-stress.
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45

Waghorn, Matthew J. "Effect of initial stand spacing and breed on dynamic modulus of elasticity of Pinus radiata." Thesis, University of Canterbury. Forestry, 2006. http://hdl.handle.net/10092/1129.

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Wood stiffness or modulus of elasticity (MOE) is one of the most important wood properties for solid timber applications, and as such, the efficacy of wood use, especially for structural timber is strongly related to MOE. MOE in Pinus radiata is highly variable and poorly understood. In this study, the effect of initial stand spacing and breed on outerwood MOE and the vertical distribution of MOE of Pinus radiata was assessed. Understanding positive or negative influences of growth caused by initial stand spacing and genetic material on MOE is appealing because it could enable us to better comprehend how forest growers could adapt silvicultural operations to the demands of wood processing. Physical characteristics of different breeds and propagation methods of Pinus radiata were assessed at a variety of initial stand spacings. Stem diameter, crown height, stem slenderness and branch size were all heavily influenced by stand spacing. Breed had a marginally significant influence on diameter and stem slenderness. Internode length was not affected by stand spacing, but showed sizeable differences, especially between the long internode 870 breed and the remaining growth and form (GF) breeds. Outerwood MOE was significantly (P<0.0001) influenced by stand spacing and breed, but not their interaction (P>0.05). MOE scaled positively with stand spacing. MOE increased by 39% from 5.4 GPa at 209 stems ha-1 to 7.5 GPa at 2551 stems ha-1. The majority of this increase (33%) occurred between 209 and 835 stems ha-1. Physiologically aged cuttings of greater maturation status exhibited greater MOE, with the three-year-old cuttings being stiffer than the one-year-old cuttings, seedlings from the 870, 268 and 850 series, by 15, 17, 22 and 27%, respectively. Stem slenderness exhibited the strongest significant (P<0.0001) relationship with MOE (r2=0.49), followed by green crown height (r2=0.46) and diameter (r2=0.44). Stem slenderness and green crown height had a direct influence on MOE that explained 53% of the variance in MOE. MOE was also significantly (P<0.0001) influenced by spacing and breed when using the resonance technique to assess whole stem MOE. The vertical distribution of MOE showed that the lowest portion of the stem (bolt 1) was approximately 30% less stiff than bolts 2 and 3. After the greatest MOE value had been obtained at bolt 3, MOE gently declined to the top of the measured stem. Variation of MOE within trees was significant (58%) at the high stockings of 1457 and 2551 stems ha-1, but somewhat lower (36%) at the lower stockings. The 870 breed was approximately 8% and 16% stiffer than the 268 and 850 breeding series respectively, across all stockings, with the three-year-old cuttings being 7% stiffer than the one-year-old cuttings. At stockings of 481 stems ha-1 and less, the proportional height at which MOE was greatest within a tree was between 25% and 50% of stem height. At stockings above 481 stems ha-1 the proportional height at which maximum MOE was obtained was between 15% and 40% of stem height. Bolt slenderness was found to be the most significant factor impacting on MOE of the bolt. Regression of critical buckling height against diameter at ground level yielded a scaling exponent of 0.55, which was lower than the scaling exponent of 0.67 predicted with constant density-specific stiffness. There was a tendency for some bolts with lower mean diameter to display significantly higher safety margins than bolts with higher mean diameter, suggesting that the largest bolts, which occur at the base of tree, are the point of most likely critical failure.
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46

Santiago, Luiz Fernando Frezzatti. "Carcterização da influência da velocidade de corte, pressão e granulometria de lixa no lixamento plano do Pinus elliottii /." Guaratinguetá : [s.n.], 2011. http://hdl.handle.net/11449/94399.

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Orientador: Manoel Cleber de Sampaio Alves
Coorientador: Marcos Tadeu Tiburcio Gonçalves
Banca: Marcos Valério Ribeiro
Banca: Eduardo Carlos Bianchi
Resumo: No presente trabalho é válido o processo de lixamento da matéria de Pinus elliottii. O objetivo principal do estudo foi entender a influência e interação dos fatores de entrada (granulometria de lixa, velocidade de corte e pressão) sobre as variáveis de saída (taxa de remoção de material, temperatura, rugosidade, potência consumida, força de lixamento, emissão acústica e integridade superficial no processo de lixamento plano da madeira Pinus elliottii, processado paralelo às fibras. O lixamento foi realizado em uma lixadeira plana com sistema de monitoramento e aquisição de dados. Utilizou-se um delineamento de blocos completamente aleatorizados para a realização do experimento. Foram ulitizados quatro tipos de granulometrais de lixa, três velocidades de corte e três pressões, com seis repetições para cada combinação totalizando 216 tratamentos. Os resultados foram analizados através de uma análise de variância (ANOVA) com nével de significância de 5%. para taxa de remoção de material foi observado que a granulometria de lixa, pressão e velocidade influenciaram significativamente. Com relação à temperatura, somente a granulometria de lixa teve uma influência significativa no aquecimento do sistema. Para o acabamento superficial, apenas a granulometria de lixa influenciou significativamente na rugosidade. O consumo de potência foi influenciado pela velocidade de corte e pressão. Para a força de lixamento, a granulometria de lixa e a pressão influenciaram significativamente. Na emissão acústica somente a granulometri de lixa influenciou significativamente no sinal captado. Para a análise de imagens foram observados diferenças no acabamento conforme se aumenta a granulometria da liza. Não foi observada nenhuma interação significativa entre os fatores velocidade de corte e pressão para todas as variáveis de saída estudadas
Abstract: This study refers to about sanding process of Pinus elliottii wood following the direction of grain. The first aim of this work is trying to undersand the influence of the following factors: belt speed, pressure and grit size on the output parameters of material remove rate, temperature, roughness, image, analysis, cutting force, power consumption and acoustic emisson. It was used a sanding belt with a data acquisition system to record the output variables. For the experiment it was used a randomized block design. The level of factors consider in the experiment it were four size of grit, three levels of pressure and three levels of belt speed. The experiment total treatments of belt speed, pressure and grit size (3 x 3 x 4=36 ) was run with six replicates for a total 216 expeiments. The results of output parameters were analyzed through the analysis of variance (ANOVA) with level of significance 5%. All the factors were significant to material remove rate. Only grit sizes were significant to the differnt levels temperature. The same behavior it was observed to the roughness where only grits size were significant. Differently the power consumption was not significant to the grits size but it was significant to the levels of pressure and belt speed. It was observed that grits sizes and pressure caused significant influence on cutting force. Only grits size significant to the acoustic emission. It was observe on analysis of image that the coarse grit produces a rougher surface than the smooth grit and anatomical elements showed up more when smooth grit was used. It could not found any interaction between the factors to all outputs parameters
Mestre
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47

Mori, Fernando [UNESP]. "O mecanismo do polo do píon e a perda de energia da SN1987 A." Universidade Estadual Paulista (UNESP), 1992. http://hdl.handle.net/11449/132648.

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48

Mori, Fernando. "O mecanismo do polo do píon e a perda de energia da SN1987 A /." São Paulo : [s.n.], 1992. http://hdl.handle.net/11449/132648.

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49

Nascimento, Angela Longo do. "Influência do cimento endodôntico e agente cimentante na retenção de pinos de fibra." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128193.

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Objetivos: O objetivo desse estudo foi avaliar a influência da presença do cimento endodôntico e agente cimentante na retenção de pinos de fibra. Metodologia: Cento e oitenta dentes extraídos foram divididos em dois grupos (n=90) de acordo com a forma de obturação: condensação lateral ou obturação apenas do terço apical. Cada um destes grupos foi subdividido em três grupos (n=10) de acordo com o cimento utilizado para a obturação (AH Plus, Endofil e MTAFillapex). Os cimentos foram manipulados e acrescidos de corante Rodamina B na proporção de 0,1% para possibilitar visualização através da microscopia confocal a laser. Quinze dias após a obturação, estes dentes foram preparados para a cimentação do pino de fibra (Reforpost Angelus) com os cimentos RelyX ARC (ARC), U200 e Gold Label Cement Lining (GL). Os dentes foram seccionados transversalmente para obtenção de fatias com 1mm de espessura e submetidos à microscopia confocal a laser para verificar a penetração do cimento endodôntico nos túbulos dentinários, posteriormente ao teste de push-out. O padrão de falha foi analisado em esteromicroscópio e imagens representativas foram feitas em microscopia eletrônica de varredura. Os valores de resistência de união em MPa de acordo com a técnica de obturação foram analisados pelo teste de Mann-Whitney. Os valores de resistência de união dos grupos experimentais foram analisados pelo teste de Kruskal-Wallis e post hoc de Dunn, com nível de significância de 5%. Resultados: Não houve diferença significativa entre as formas de obturação (P>0,05). O tipo de cimento obturador influenciou a resistência de união, e o cimento MTA-Fillapex apresentou valores de resistência de união significativamente inferiores ao AH Plus (P<0,05). Os grupos que utilizaram GL para cimentação dos pinos de fibra de vidro apresentaram valores para o teste de push-out superiores aos cimentos resinosos (P < 0,05). Não houve diferença significativa entre o ARC e o U200 (P > 0,05). Conclusões: Valores de resistência de união mais altos foram observados quando os pinos de fibra foram cimentados com cimento GL . Os padrões de falha mistas foram predominantes e ocorreram em todos os grupos experimentais.
Aim: Evaluate the influence of the endodontic sealer and luting cements on the fiber post bond strength. Methodology: One hundred and eighty extracted teeth were assigned to two groups, considering the root filling technique: lateral condensation or root filling of the apical portion only. Each group were divided into three groups (n=10) according the sealer applied (AH Plus, Endofill or MTA-Fillapex). Rhodamine B was mixed to the sealer in a ratio of 0,1% in order to provide adequate fluorescence assessed by confocal microscopy. Fifty days after root canal filling, post-space preparation were performed with luting cements: RelyX ARC (ARC), U200 and Gold Label Cement Lining (GL). One thick slices were produced and submitted to confocal miscroscopy to assessed sealer penetration into dentinal tubules, and than submitted to push-out test. The failure modes were analysed in stereomicroscope and representative images were obtained in a scanning electron microscope. Push-out strength values of the root filling technique were analyzed using Mann-Whitney test. Push-out strength values of experimental groups were analysed using Kruskal-Wallis and Dunn´s post hoc test at significance level 5%. Results: No significant difference was observed (P>0.05) between the root filling technique. The type of endodontic sealer influenced the push-out bond strength, and MTA-Fillapex sealers presents lower bond strength values than AH Plus (P<0.05). Fiber posts cemented with GL presented higher push-out bond strength than resin cements (P<0.05). There was no significant difference between ARC and U200 (P>0.05). Conclusions: Fiber posts showed higher bond strength values when cemented with GL. Mixed failures were predominant and occurred in all the experimental groups.
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50

Vanc, Ondřej. "Taxonomické zhodnocení Pinus contorta subsp. Latifolia (Engelm.) na výsypkových stanovištích a možnosti jejího využití." Master's thesis, Česká zemědělská univerzita v Praze, 2016. http://www.nusl.cz/ntk/nusl-260379.

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Abstract:
Lodgepole pine is exotic species of pine originating from North America (Canada, United States, United Mexican States), where it occurs along the Pacific coast. This is a very compatible species because, despite a plethora of geomorphological habitats has created a total of five subspecies, while the Czech Republic there are three of them. They are: Shore pine (Pinus contorta subsp. contorta), Lodgepole pine (Pinus contorta subsp. latifolia), Murray pine (Pinus contorta subsp. murrayana). Occurrence of Pinus contorta was recorded in nine counties, twenty and twenty-three districts of municipalities with extended powers. The total stand area was found to 128.66 hectares. When finding that Pinus contorta in our conditions is described as exotic plants. As a gateway for non-native landscape landscape that is post-mining areas. Use of Lodgepole pine was thus deemed appropriate. Uncultured landscape together with wood unoriginal see to it that the uncultured landscape becomes a landscape rich in diversity. Lodgepole pine, of course, is not the only species that was about it all taken care of. Its suitability was chosen because of its low demands on soil, hydrological and climatic conditions, including frost hollows at elevations 2,500 meters above sea level. Which in the Czech Republic or cannot be used because it is our highest point 1,602 meters above sea level. The effort was to map Lodgepole pine throughout the Czech Republic, where it would be clearly seen where the forest vegetation on which the administrative territory of the Lodgepole pine occur. This reliance on the willingness of administrators data information, which for our purposes were considered Institute of Forest Management, where we were given virtually everything to us this institution has been able to provide. Another institution, where we were given also all the military management of forests and farms. Unfortunately, the state enterprise Forestry of the Czech Republic, as majority owner of primary forests in the Czech Republic, was not willing to provide the requested information on the matter on Lodgepole pine, forest management Děčín only the necessary information. Given that this work was originally conceived to Pinus contorta subsp. latifolia, while work was concluded that Pinus contorta subsp. latifolia is a segmentation occurring geographic subspecies that was not able to clearly identify the data that we had available so this work deals with Lodgepole pine at the species level and the resulting map outputs in the results of the work 7 were processed in the geographic information systems, which managed to get stand up to the level surface (ha) in the regions of municipalities with extended powers.
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