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Experimental Acquisition and Characterisation of Large-Scale Flow Structures in Turbulent Mixed ConvectionSchmeling, Daniel 02 July 2014 (has links)
No description available.
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Open Pit Truck /shovel Haulage System SimulationCetin, Necmettin 01 October 2004 (has links) (PDF)
This thesis is aimed at studying the open pit truck- shovel haulage systems using computer simulation approach. The main goal of the study is to enhance the analysis and comparison of heuristic truck dispatching policies currently available and search for an adaptive rule applicable to open pit mines. For this purpose, a stochastic truck dispatching and production simulation program is developed for a
medium size open pit mine consisting of several production faces and a single dump site using GPSS/H software. Eight basic rules are modeled in separate program files. The program considers all components of truck cycle and normal
distribution is used to model all these variables. The program asks the user to enter the number of trucks initially assigned to each shovel site.
Full-factorial simulation experiments are made to investigate the effects of several factors including the dispatching rules, the number of trucks operating, the number of shovels operating, the variability in truck loading, hauling and return
times, the distance between shovels and dump site, and availability of shovel and truck resources. The breakdown of shovel and trucks are modeled using exponential distribution. Three performance measures are selected as truck production, overall shovel utilization and overall truck utilizations. Statistical analysis of the simulation experiments is done using ANOVA method with Minitab software. Regression analysis gives coefficient of determination values,
R2, of 56.7 %, 84.1 %, and 79.6 % for the three performance measures, respectively. Also, Tukey&rsquo / s method of mean comparison test is carried out to compare the basic dispatching rules. From the results of statistical analysis, it is
concluded that the effects of basic truck dispatching rules on the system performance are not significant. But, the main factors affecting the performances are the number of trucks, the number of shovels, the distance between the shovels
and dump site, finally the availability of shovel and truck resources. Also, there are significant interaction effects between these main factors. Finally, an adaptive rule
using the standardized utilization of shovels and trucks is developed.
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Habitat selection and food-web relations of Horned Grebes (Podiceps auritus) and other aquatic birds on constructed wetlands in the Peace Parkland, Alberta, CanadaKuczynski, Eva C 11 1900 (has links)
I investigated if constructed wetlands provide breeding habitat for the Horned Grebe (Podiceps auritus) in northwest Alberta. Over two years, I conducted bird surveys of 201 borrow-pits (ponds created during road construction) and 18 natural wetlands and collected data on local habitat and landscape features. For subsets of ponds, I also collected water chemistry and invertebrate data, and conducted stable isotope analysis. Grebes occurred on 36% of borrow-pits and produced chicks on 61% of occupied sites in 2007 and 81% in 2008. Grebes occurred more frequently on larger ponds, with more emergent vegetation, and avoided forested ponds that supported beaver activity. Horned Grebes are generalist foragers that did not select nesting ponds based on food-web structure. Twenty-six other bird species used borrow-pits, with distinct assemblages occurring on agricultural versus forested ponds. My study indicates that wetland construction offers a viable method for creating habitat for Horned Grebes and other species. / Ecology
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Schwallwellen infolge der Bewegung einer BegrenzungsflächeRöhner, Michael 29 September 2011 (has links) (PDF)
Restlöcher ausgekohlter Braunkohlentagebaue werden aus landeskulturellen und ökonomischen Gründen wasserwirtschaftlich als Speicher, Hochwasserrückhaltebecken, Klärteiche, Wassergewinnungsanlagen sowie zur Naherholung genutzt. Diese Restlöcher werden zum großen Teil von aus geschüttetem Abraum bestehenden Böschungen umschlossen. Bei Wasserspiegelschwankungen neigen diese unbefestigten Böschungen zum Rutschen. Als Folge dieser Böschungsrutschungen bilden sich auf der Wasseroberfläche Wellen, die eine beachtliche Größe erreichen können. Diese Schwallwellen übertreffen in ihren Ausmaßen die Windwellen in den Tagebaurestlöchern um ein Vielfaches. Um diese Erscheinungen vorausberechnen zu können, wurden im Hubert-Engels-Laboratorium der Sektion Wasserwesen Untersuchungen durchgeführt.
Die Entwicklung einer allgemeingültigen Berechnungsmethode für die Schwallwelle bei der Bewegung eines Teiles der das Wasserbecken begrenzenden Böschung verlangt die Einführung erfassbarer Parameter wie der Breite der rutschenden Böschung, den zeitlichen Verlauf der Wasserverdrängung sowie Tiefen- und Lageverhältnisse des Beckens. Die dafür notwendigen Kennzahlen können nur näherungsweise bestimmt werden, so dass einfache Beckengeometrien, ein über die Rutschzeit gleich bleibender Verlauf der Wasserverdrängung und Erhaltung der Böschungskante einem Berechnungsverfahren zugrunde gelegt werden müssen.
Für die Berechnung des Füllschwalles auf das ruhende Wasser sind einige Verfahren bekannt geworden, die auf eine gemeinsame Gleichung für die Berechnung der Schwallhöhe zurückzuführen sind. Für die ebene Ausbreitung des Füllschwalles über Ruhewasser ergeben sieh zwei prinzipielle Abflussmöglichkeiten: Auflösung in Wellen oder brandender Schwallkopf. Diese beiden Möglichkeiten sowie der Übergangsbereich werden durch FROUDE-zahlen festgelegt.
Der Wellenkopf von Füllschwallwellen wird durch eine Einzelwelle gebildet.
Die Rutschung einer Böschung wurde durch die gleichzeitige Horizontal- und Vertikalbewegung einer Platte nachgebildet. Die Bewegung der Platte, die entstehenden Wellen und die Kräfte auf Auflaufböschung wurden durch einen Oszillografen aufgezeichnet.
Die Auswertung der Versuche ergab eine Übereinstimmung zwischen Messergebnissen und den Berechnungen nach den Gesetzen des Füllschwalls. Die sekundlich verdrängte Wassermenge pro Breiteneinheit und die Ruhewassertiefe bestimmen die entstehenden Schwallwellen. Ein Einfluss der vertikalen Bewegungskomponente ist im untersuchten Bereich nicht nachweisbar. Die dynamischen Kräfte auf die Abschlussböschung können durch den Impuls der Einzelwelle dargestellt werden.
Die räumliche Ausbreitung der Schwallwellen wurde in einem Modell untersucht. Dabei wurde festgestellt, dass die größten Wellenhöhen in der Richtung der Bewegung der Platte auftreten, während die Wellenhöhen in seitlichen Ausbreitungsrichtungen kleiner sind.
Berechnungsansätze für die maximale Wellenhöhe der front wurden ermittelt.
Als Ergebnis wurde ein Berechnungsverfahren entwickelt, welches ausgehend von den Parametern dar Rutschung, die Eigenschaften der Schwallwellen einschließlich der durch sie hervorgerufenen Belastungen auf der Auflaufböschung ermöglicht. Mit diesem Berechnungsverfahren ist es möglich, Böschungen wirtschaftlich zu gestalten und schädliche Rückwirkungen auf das Staubecken durch Schwallwellen zu vermeiden. Bisher notwendige Kosten für eine sehr flache Gestaltung der Böschung können entfallen. Gleichzeitig bleibt ein größerer nutzbarer Stauraum erhalten.
Die Digitalisierung der vorliegenden Arbeit durch die Sächsische Landesbibliothek - Staats- und Universitätsbibliothek Dresden (SLUB) wurde durch die Gesellschaft der Förderer des Hubert-Engels-Institutes für Wasserbau und Technische Hydromechanik an der Technischen Universität Dresden e.V. unterstützt.
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Med älgen i huvudrollen : Om fångstgropar, hällbilder och skärvstensvallar i mellersta Norrland / Staging the elk : On pitfalls, rock art and mounds of burnt stone in northernmost SwedenSjöstrand, Ylva January 2011 (has links)
The importance of the elk (Alces alces) in the Stone Age societies of northern Sweden constitutes the major focus of this thesis. The point of departure is a simple but crucial observation: this animal is the common denominator between the three stationary types of remains known in this region from the period 4000-1800 BC. Here, I refer to the pit falls, the rock art sites, and the mounds of burnt stone. Pit falls have been used for trapping elks, and can be found on the migration trails that have been used by these animals for thousands of years. On the rock art sites, the elk constitutes the most frequently depicted motif, and the mounds of burnt stones contain extremely large quantities of elk bones. If the elk had not held a central position in the life world of prehistoric people in the northern Swedish region of Norrland, these archaeological materials would certainly have had a different appearance. I claim that it is the significance of this animal that has led to, and shaped, the emergence of these material remains. In this study the overall importance of the elk is investigated. My main question is how the elk’s significance affected the prehistoric societies of Norrland. I found that the elk’s material remains led to a range of consequences. The pit falls, rock art sites and mounds of burnt stone tied the prehistoric people to certain areas in the landscape. However, at the same time, these remains required to be constantly in transformation to be usable. Pit falls, for example, have to be re-digged in order to at all function as traps for big game. The conceptual dichotomy between permanence and change can be traced in the ways in which the elk motif at the rock art site at Nämforsen was altered. The elk figures are depicted with either straight or angled legs. I interpret this variation as an indication of the fact that the elk motif functioned as a key symbol – a motif that is able to express a range of meanings when it becomes altered and varied. The emergence of depicting the opposition between mobility and permanence tells us that the Stone Age societies had problems uniting these two concepts. I interpret this as signifying that these hunter-gatherers became aware of the “Neolithic aspects” of their own social structure.
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Variability in late prehistoric prey-use strategies of the southeastern Columbia Plateau a test using the Harder Site faunal assemblage /Kimball, Vaughn R., January 2005 (has links) (PDF)
Thesis (M.A.)--Washington State University, 2005. / Title from PDF t.p. (viewed on Nov. 6, 2005). Includes bibliographical references (p. 75-84).
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Atypické pohřbívání ve středověkých Čechách / Atypical burials in medieval BohemiaHLADÍKOVÁ, Miroslava January 2011 (has links)
Tthis presented work is focused on a issue of atypical burials in medieval Bohemia. There are groups of people and the reasons which they led a community to such an action at that time. This work contains a summary of selected sites with the mentioned specific graves. Analysis and evaluation of character and significance of atypical burials in a medieval community is a part of this work.
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Análise morfológica de pites em aços inoxidáveis austeníticos ABNT 304 e 310S submetido à nèvoa salinaRibeiro, Rosinei Batista [UNESP] January 2004 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:59Z (GMT). No. of bitstreams: 0
Previous issue date: 2004Bitstream added on 2014-06-13T20:27:46Z : No. of bitstreams: 1
ribeiro_rb_dr_guara.pdf: 6899626 bytes, checksum: 243c390b34b8f55eaccd7334a877efe4 (MD5) / Este projeto de pesquisa teve como objetivo estudar toda evolução que governa o crescimento, distribuição e classificação dos pites em aços inoxidáveis austeníticos ABNT 304 e 310S obtidos no estado como recebido e tratados, submetidos a diferentes tempos de exposição em névoa salina. A originalidade deste trabalho baseou-se no desenvolvimento de uma técnica para caracterização morfológica e da corrosão localizada associando com os aspectos de descrição de formas, tamanho, parâmetros específicos e populacionais. O aço inoxidável 304 apresentou morfologia irregulares > região de transição A> cônicos >hemisféricos > região de transição B, sendo que irregulares e região de transição A em maiores quantidades no sistema. Na liga tratada a cada tempo de exposição, a quantidade de pites é da mesma ordem, ou seja, região de transição A, irregulares, cônicos, hemisféricos, região de transição B, sendo que os pites na região de transição A e irregulares estão presentes em maior quantidades no sistema. O aço inoxidável 310S, como recebido, exibiu a seguinte morfologia: pites hemisféricos > região de transição A > região de transição B > irregulares > cônicos, sendo que os pites estão presentes em maiores quantidades em: hemisféricos e região de transição A. A quantidade de pites na liga tratada a cada tempo de exposição é da mesma ordem: região de transição B > hemisféricos > região de transição A > cônicos >irregulares. O aço inoxidável 304 apresentou maior resistência à corrosão por pite do que o aço inoxidável 310S, e também diferenças na distribuição, classificação e mediana dos tamanhos dos pites, conforme os resultados obtidos na avaliação estatística da superfície e perfis dos mesmos. / This research project has had as objective to study all evolution that governs the growth, distribution and classification of pits in ABNT 304 and 310S austenitic stainless steels obtained in the state as receveid and treated, submitted to different times of exposition in saline mist. The originality of this work has been based on the development of a technique for morphologic characterization and of located corrosion associating with the shape description, size specific and population parameters. The 304 stainless steel has presented the following morphology: irregular > transition region A > conic > hemispherical > transition region B, in which irregular and transition region A > are in larger amounts in the system. In the treated alloy at each exposition time, the pits amount is at the same order, in other words, transition region A, irregular, conic, hemispherical, transition region B, in which the pits in the transtion region A and irregular are present in larger amounts in the system. The 310S stainless steel, as receveid, has exhibited the following morphology: hemispherical pits > transition region A > transtion region B > irregular > conic, in which the pits are present in large amounts in: hemispherical pits and transition region A. The pits amount in the treated alloy at each time of exposition has the same order: transition region B > hemispherical > transition region A > conic> irregular. The 304 stainless steel has presented pit corrosion resistance larger than the 310S stainless steel, and also differences in the distribution, classification and pits sizes medium, according to the results obtained in the statistical evaluation of their surface and profiles.
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Relação família-escola: uma parceria para a inclusão de alunos com altas habilidades/superdotação / Relation school-family: a partnership for inclusion of gifted and talented studentsRech, Andréia Jaqueline Devalle 06 December 2016 (has links)
School inclusion has been a challenge for many teachers who work on regular school classrooms. A
number of factors hinder the pedagogical practice of these teachers in their teaching with students
who are the target audience of special education. Besides, it is observed that, when dealing with
school inclusion of gifted and talented students (G/T), there is resistance from some teachers. This
fact lies on the lack of knowledge about the theme of G/T, which may occur due to the wrong
conceptions socially widespread, adding to that an incipient initial education in relation to G/T
students. Accordingly, it is necessary to create support networks so that school inclusion of G/T
students becomes effective. In this sense, the family could be a support network and set up a
partnership with the school. Thus, both can articulate and organize a collaborative work on behalf of
school inclusion of the G/T child. After reflecting about the situation exposed, this study proposes the
following thesis: school inclusion of the G/T child can be effective when family and school act in
conjunction in this process, eliminating/diminishing the barriers that hinder this partnership, since the
family can influence the school inclusion of the G/T child. This study included 12 families with children
identified as G/T more than a year ago, and regularly attended the Giftedness Incentive Program (GIP)
during the year of 2014, seven special educators, six teachers from early grades and five counseling
teachers that, in the year of 2015, worked with G/T students. Regarding the method, the study case
within the qualitative approach was chosen. The instruments of data collection selected were:
narrative interview, Questionnaire of Family System Characterization Version – Parents or Guardians
(DESSEN, 2011), Checklist of Shared Routine and Engagement between Family-school, Version for
Teachers, and Checklist of Shared Routine and Engagement between Family-school, Version for
Parents (mother, father, or guardian), both validated by Dessen and Polonia (2011). The interviews
were analyzed qualitatively and from the analysis of frequency, through categories already defined by
the authors of the instrument. The final considerations point to a relation between family and school
that is still incipient, due to the fact that some barriers/constraints were identified, having prevailed an
accusative relationship, which may be hindering the construction of a partnership relation. There were
specific cases in which there was conjunction between both institutions, and that result in greater
influence/participation of the family in the school life of the G/T child. Therefore, the study raises the
need to offer continuous education for both the family and the school, aiming at broadening the debate
regarding the importance that both have in creating a support network so that, together, they can
articulate actions on behalf of school inclusion of the child who is also a G/T student. / A inclusão escolar tem sido um desafio para muitos professores que atuam nas classes regulares de
ensino. Diversos fatores dificultam a prática pedagógica desses em sua atuação com os alunos que
constituem o público-alvo da educação especial. Além disso, observa-se que, quando se trata da
inclusão escolar dos alunos com altas habilidades/superdotação (AH/SD), há resistência por parte de
alguns professores. Esse fato reside no desconhecimento da temática das AH/SD, decorrente,
possivelmente, das concepções equivocadas difundidas socialmente, somado a uma formação inicial
incipiente no que se refere aos alunos com AH/SD. Sendo assim, é necessário formar redes de apoio
para que se efetive a inclusão escolar do aluno com AH/SD. Nesse sentido, a família pode ser uma
rede de apoio e tornar-se parceira da escola. Assim, ambas podem se articular e organizar um
trabalho colaborativo em prol da inclusão escolar do filho/aluno com AH/SD. Após refletir sobre as
situações expostas, propõem-se a seguinte tese: a inclusão escolar do filho/aluno com AH/SD será
efetivada quando a família e a escola atuarem de forma articulada nesse processo, eliminando as
barreiras que dificultam essa parceria, uma vez que a família constitui-se como influente na inclusão
escolar do filho com AH/SD. Para verificar a tese, o objetivo geral foi compreender a articulação entre
família e escola, verificando as barreiras que dificultam essa parceria, além de visualizar possíveis
influências da família no processo de inclusão escolar do filho/aluno com AH/SD. Participaram da
pesquisa 12 famílias com filhos identificados com AH/SD há mais de um ano e que foram assíduos
durante o ano de 2014 no Programa de Incentivo ao Talento (PIT), sete educadores especiais, seis
professores dos anos iniciais e cinco professoras conselheiras que, no ano de 2015, atuaram com os
alunos com AH/SD. Em relação ao método, optou-se pela abordagem qualitativa, do tipo estudo de
caso. Os instrumentos de coleta de dados selecionados foram: entrevista narrativa, Questionário de
Caracterização do Sistema Familiar Versão – Pais ou Responsável (DESSEN, 2011), Checklist da
Rotina Compartilhada e Envolvimento entre Família-escola, Versão para Professores e Checklist da
Rotina Compartilhada e Envolvimento entre Família-escola Versão Pais (mãe, pai ou responsável),
ambos validados por Dessen e Polonia (2011). As entrevistas foram analisadas de forma
qualitativa/descritiva articulada com o referencial teórico que subsidiou a tese. Os Checklists foram
analisados qualitativamente e a partir da análise de frequência, por meio de categorias já
determinadas pelas autoras dos instrumentos. As considerações finais apontam para uma relação
entre família e escola ainda incipiente, pois algumas barreiras/entraves foram identificadas, tendo
prevalecido uma relação acusativa, o que pode estar dificultando a construção de uma relação de
parceria. Foram pontuais os casos em que houve uma articulação entre ambas as instituições e que
tenham como resultado maior influência/participação da família na vida escolar do filho com AH/SD.
Portanto, sinaliza-se a necessidade de ofertar uma formação continuada tanto para a escola quanto
para a família, visando ampliar o debate para a importância de ambas formarem uma rede de apoio
para que juntas articulem ações em prol da inclusão escolar do filho que também é aluno com AH/SD.
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Avaliação in vitro de propriedades mecânicas, químicas e antimicrobianas de um selante de fossas e fissuras isento de bisfenol A / In vitro evaluation of mechanical, chemical and antimicrobial properties of a bisphenol A-free pit-and-fissure sealantSoraia Monique Fiorati Aguiar 21 May 2010 (has links)
Tendo em vista o importante papel desempenhado pelos selantes de fossas e fissuras na prevenção da cárie dental, o objetivo do presente estudo foi avaliar in vitro propriedades mecânicas, químicas e ntimicrobianas do selante isento de bisfenol A Embrace Wetbond™. Para os testes de resistência ao cisalhamento e microinfiltração foram selecionados 135 terceiros molares hígidos, extraídos de humanos, divididos aleatoriamente em 6 grupos: (I) selante Fluroshield® sem contaminação; (II) selante Embrace Wetbond™ sem contaminação; (III) selante Fluroshield® contaminado com saliva; (IV) selante Embrace Wetbond™ contaminado com saliva; (V) selante Fluroshield® contaminado com água; e (VI) selante Embrace Wetbond™ contaminado com água. No estudo de resistência ao cisalhamento os dentes foram seccionados no sentido vestíbulo-lingual, a porção radicular removida e as superfícies mesiais e distais foram embebidas em resina de poliéster. Após o condicionamento do esmalte, foi aplicado o selante com o auxílio de uma matriz de Teflon®. Os espécimes foram termociclados e submetidos ao teste de resistência ao cisalhamento com uma velocidade de 0,5mm/min e célula de carga de 50kgf. Os resultados foram comparados empregando a análise de variância (ANOVA) e pós-teste de Tukey. No estudo de microinfiltração, após o condicionamento do esmalte foi aplicado o selante. Os dentes foram termociclados, selados na região da câmara pulpar com resina composta, isolados, imersos em solução de rodamina B a 0,2%, incluídos em resina acrílica, seccionados, lixados, montados em lâminas, identificados e analisados em microscópio óptico para quantificação da microinfiltração. Os resultados foram comparados empregando o teste de Kruskal-Wallis e o pós-teste de Dunn. No estudo de liberação de fluoreto por meio de água aquecida e saliva artificial foram selecionados dois selantes resinosos contendo fluoreto (Embrace Wetbond™ e Fluroshield®), uma resina composta micro-híbrida (FiltekTM Z-250) e um cimento de ionômero de vidro (Vidrion R). As determinações de fluoreto foram realizadas por potenciometria direta, utilizando o eletrodo seletivo combinado de fluoreto. Para o teste de liberação de fluoreto em saliva artificial foram confeccionados 8 corpos de prova de cada material , os quais foram armazenados em tubos plásticos contendo saliva artificial, substituída diariamente. Após 15 dias, foi avaliada a quantidade de fluoreto liberado nas soluções. Os valores obtidos em mV foram convertidos em ppm (μg/ml). Os resultados foram comparados empregando a análise de variância (ANOVA) e o pós-teste de Tukey. No estudo da atividade antimicrobiana, efetuado por meio do teste de difusão em ágar pelo método do poço, foram selecionados dois selantes resinosos contendo fluoreto (Embrace Wetbond™ e Fluroshield®), um cimento de ionômero de vidro (Vidrion R), solução de digluconato de clorexidina a 1% e soro fisiológico. Foram utilizadas cepas de S. mutans (ATCC 25175 e cepa de campo), na densidade de 1-2 da escala de McFarland. Após o período de incubação, a zona de inibição do crescimento microbiano foi mensurada. Os resultados foram comparados empregando a análise de variância ANOVA e o pós-teste de Bonferroni. O nível de significância em todas as análises estatísticas foi de 5%. No estudo da dosagem de bisfenol A foram selecionados dois selantes resinosos (Embrace Wetbond™ e Fluroshield®), dispensados em recipientes contendo 3ml de metanol. Após homogeneização e filtragem, os extratos foram analisados utilizando um espectrômetro de massas por cromatografia gasosa. Foram realizados testes com as fórmulas moleculares do bisfenol A (C15H16O2) e do Bis-GMA (C29H36O8). Com base nos resultados obtidos pôde-se concluir que o selante Embrace Wetbond™ apresentou resistência ao cisalhamento próxima do mínimo aceitável e alta microinfiltração, quando utilizado de acordo com as indicações do fabricante, em condições de contaminação com umidade. Por outro lado, esse selante apresentou elevada liberação de fluoreto, tanto em água aquecida quanto em saliva artificial, apresentou elevada atividade antimicrobiana e não apresentou liberação de bisfenol A e de Bis- GMA. / Considering the important role of pit-and-fissure sealants on the prevention of dental caries, the purpose of this study was to evaluate in vitro the mechanical, chemical and antimicrobial properties of the bisphenol A-free pit-and-fissure sealant Embrace Wetbond™. For the shear bond strength and microleakage tests, 135 sound human third molars were selected and randomly assigned to 6 groups: (I) Fluroshield® sealant without contamination; (II) sealant Embrace Wetbond™ without contamination; (III) Fluroshield® sealant contaminated with saliva; (IV) Embrace Wetbond™ sealant contaminated with saliva; (V) Fluroshield® sealant contaminated with water; and (VI) Embrace Wetbond™ sealant contaminated with water. For the shear bond strength test, the teeth were sectioned in a buccolingual direction, the root portion was removed and the mesial and distal surfaces were embedded in polyester resin. The sealant was applied to the acid-etched enamel with the aid of Teflon® matrix. The specimens were thermocycled and subjected to a shearing force at a crosshead speed of 0.5mm/min with a 50kgf load cell. Data were analyzed statistically by analysis of variance (ANOVA) and Tukeys post-test. For the microleakage assay, after acid etching of enamel, the teeth were thermocycled, the pulp chamber was sealed with composite resin, and the teeth were rendered waterproof, immersed in 0.2% B rhodamine solution, embedded in acrylic resin, sectioned, ground, mounted on glass slides, identified and analyzed with an optical microscope for quantification of microleakage. The results were compared by the Kruskal-Wallis and Dunns post-test. Two fluoride-containing resin sealants (Embrace Wetbond™ and Fluroshield®), a microhybrid composite resin (FiltekTM Z-250) and a glass ionomer cement (Vidrion R) were selected for the fluoride release test in heated water and artificial saliva. Fluoride measurements were performed with a direct potentiometry using a fluoride ion selective electrode. For the test in saliva artificial, 8 specimens of each material were fabricated and stored in plastic tubes containing artificial saliva, which as daily renewed. The amount of fluoride released in the solutions after 15 days was analyzed, and the the values obtained in mV were converted into PPM (μg/mL). The results were compared by ANOVA and Tukeys post-test. Two fluoride-containing resin sealants (Embrace Wetbond™ and Fluroshield®), a glass ionomer cement (Vidrion R), 1% chlorhexidine digluconate solution and saline were selected for the analysis of the antimicrobial activity using the agar-well diffusion assay. Suspensions of S. mutans strains (ATCC 25175 and field strain) with density equivalent to the 1-2 McFarland scale were used. After incubation, the zones of microbial growth inhibition were measured. The results were compared by ANOVA and Bonferroni post-test. A significance level of 5% was set for all statistical analyses. For the analysis of bisphenol A dosage, two resin sealants (Embrace Wetbond™ and Fluroshield®) were delivered in receptacles containing 3ml of methanol. After homogenization and filtering, the extracts were analyzed under gas chromatography-mass spectroscopy and tests were performed with the molecular formulas of bisphenol A (C15H16O2) and Bis-GMA (C29H36O8). Based on the obtained results, it may be concluded that the sealant Embrace Wetbond™ presented shear bond strength near of the minimum acceptable and great microleakage when used according to the manufacturers instructions under moisture contamination conditions. On the other hand, this sealant presented high fluoride release in both heated water and artificial saliva, showed high activity antimicrobial and did not present release of bisphenol A or Bis-GMA.
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