Coral bleaching is a worldwide result of climate change that is affecting the marine ecosystems greatly. Methods to help solve the issue have been previously explored and Beneficial Microorganisms for Corals (BMCs) have been proven to help mitigate coral bleaching in laboratory trials. In their efforts to test its effectiveness on the field, scientists have found that it would be beneficial to have a constant, biocompatible, source of BMCs. We have tested Calcium Alginate microspheres, what we call Alginate Beads, in terms of release rate and cell viability to determine if they are fit to be used as vectors for the BMC consortia. By placing the Beads in two different temperatures representing winter and summer temperatures in the Red Sea in agitation we were able to understand their dynamics more clearly. By using Flow Cytometry, Colony Forming Units, and microscopy techniques we were able to see that Alginate Beads incorporate bacteria into their matrix and keep them viable for up to two weeks. We also observed that the Beads release more bacterial cells at higher temperatures compared to lower temperatures. This suggests that when used in the field, Alginate Beads are able to sustain the bacteria for a prolonged time period and it will release bacteria at a higher rate in warmer temperatures potentially either season or region-wise. Hence, we believe that Alginate Beads could be suitable as vectors for field research and should be explored further.

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Submitted by Eunice Novais (enovais@uepg.br) on 2018-07-24T17:00:57Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Biancamedeirosmaran.pdf: 3971508 bytes, checksum: 0188e5172bf200ce9a76e85bec1691c9 (MD5) / Made available in DSpace on 2018-07-24T17:00:57Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Biancamedeirosmaran.pdf: 3971508 bytes, checksum: 0188e5172bf200ce9a76e85bec1691c9 (MD5) Previous issue date: 2018-06-08 / Objetivos: Avaliar a eficácia e sensibilidade dental (SD) utilizando agentes dessensibilizantes incorporados ao gel no clareamento caseiro (1) e em consultório (2), no uso da ativação com luz no clareamento em consultório com alta e baixa concentração de peróxido de hidrogênio (3 e 4); no clareamento combinado (consultório e caseiro) vs. isolado (5), além de avaliar a conformidade dos estudos clínicos randomizados (ECRs) de clareamento com o CONSORT e o risco de viés desses estudos pela ferramenta Cochrane (6). Metodologias: Para este trabalho, foram feitos seis estudos: dois ECRs e quatro revisões sistemáticas (RSs), sendo que o estudo (4) foi uma RS de comparação mista de tratamentos (MTC). Os ECRs (1 e 2) foram triplo-cegos, boca-dividida e o tratamento clareador foi realizado em 120 pacientes livres de cárie, conforme critérios de inclusão e exclusão, sendo 60 em cada estudo. Os agentes dessensibilizantes incorporados ao gel foram, 3% de nitrato de potássio e 0,2% de fluoreto de sódio (1), e 5% de nitrato de potássio (2). No estudo (1) uma moldeira foi usada três horas diariamente por 21 dias, no estudo (2) foi feita uma aplicação única de 50 minutos em duas sessões com intervalo de sete dias entre elas. Foram avaliados o risco absoluto e a intensidade da SD por meio das escalas visual analógica 0-10 cm e de classificação numérica 0-4 durante três semanas no estudo (1) e durante e até 48 horas após cada sessão no estudo (2); a alteração de cor foi registrada utilizando as escalas de cor Vita Classical, Bleachedguide (ΔUEV) e espectrofotômetro Easyshade (ΔE*) antes, durante e após 30 dias do término de cada tratamento. O risco absoluto e a intensidade da SD foram avaliadas pelos testes de McNemar e Wilcoxon Signed Rank, respectivamente (α = 0,05), a eficácia do clareamento foi avaliada pelos testes de Wilcoxon Signed Rank (ΔUEV) e teste t para dados pareados (ΔE*) (α = 0,05). Nas RSs (3-6) foram feitas buscas por termos específicos sobre o tema em diferentes bases de dados e literatura cinzenta. O risco de viés foi avaliado usando a ferramenta de Colaboração Cochrane. Meta-análises foram conduzidas para mudança de cor (ΔE*, ΔSGU), risco e intensidade de SD, usando modelo de efeitos aleatórios. A heterogeneidade foi avaliada com o teste Q de Cochran e a estatística I2. A qualidade de evidência (GRADE) foi avaliada nos estudos (3) e (5). Resultados: No estudo (1), não houve diferenças entre os grupos na cor, no risco e intensidade da SD (p > 0,05), já no estudo (2) foram observadas diferenças apenas na redução da intensidade da SD para o grupo com agente dessensibilizante nas primeiras 24 horas (p < 0,01). Nas RSs após a busca dos estudos, restaram 21 (3), 28 (4), 11 (5), 185 (6) ECRs. Na RS (3) não houve diferença na cor e na SD (p > 0,05), e a qualidade de evidencia foi graduada como moderada para ΔE* e risco de SD, e muito baixa e baixa para ΔUEV e intensidade da SD, respectivamente. Na RS de MTC (4), não houve diferença na cor sem o uso da luz ou com diferentes fontes de luz usadas. Na RS (5) não houve diferença na cor no clareamento combinado vs. em consultório (p > 0,05) e não foram obtidos dados disponíveis para avaliação do risco e intensidade da SD; no clareamento combinado vs. caseiro não foram observadas diferenças para ΔE*, ΔSGU e risco de SD, porém, menor intensidade de SD foi detectada no clareamento caseiro isolado com diferença de média padronizada de 0,86 (IC 95% 0,31-1,41), e a qualidade de evidência foi graduada como moderada para alteração de cor em ΔE*, e baixa ou muito baixa para as demais análises. Na RS (6) na classificação de adesão ao CONSORT dos estudos, a média geral foi 16,7 ± 5,4 pontos (de 32 pontos no total) e apenas 7,6% foram julgados como baixo risco de viés. Conclusões: A incorporação dos agentes dessensibilizantes nos géis clareadores usados neste trabalho não afetou a cor e não reduziu a SD no clareamento caseiro (1), porém diminuiu a intensidade da SD no clareamento em consultório (2). O uso da ativação com luz no clareamento em consultório não melhorou a cor nem afetou a SD independente da concentração de peróxido de hidrogênio utilizada (3) e igualmente não afetou a cor no estudo (4). No clareamento combinado vs. isolado (5), baixa intensidade de SD foi encontrada no clareamento caseiro, quando este foi realizado isoladamente. E no estudo (6) concluiu-se que a adesão ao CONSORT em ECRs de diferentes técnicas de clareamento é baixa e possuem alto risco de viés. / To evaluate efficacy and tooth sensitivity (TS) through the use of desensitizing agents incorporated into the gel in the at-home (1) and in the in-office bleaching (2), in the use of light activation in the in-office bleaching with high and low hydrogen peroxide concentration (3 and 4); in combined (at-home and in-office) vs. isolated bleaching (5), in addition to assessing the conformity of the randomized clinical trials (RCTs) of bleaching with CONSORT and the risk of bias of these studies by the Cochrane tool (6). Methodologies: Six studies: two RCTs and four systematic reviews (SRs) were made for this work, the study (4) was a mixed-treatment comparison (MTC). The RCTs (1 and 2) were triple-blind, split-mouth and the bleaching treatment was performed on 120 caries-free patients, according to inclusion and exclusion criteria, of which 60 were in each study. The desensitizing agents incorporated into the gel were 3% potassium nitrate and 0.2% sodium fluoride (1), and 5% potassium nitrate in study (2). In study (1) a tray was used three hours daily for 21 days, in study (2) a single application of 50 minutes was made in two sessions with 7-days intervals between them. Were assessed the absolute risk and the intensity of TS using the 0-10 cm visual analog and 0-4 numerical rating scales for 21 days in the study (1) and during 48 hours after each study session (2); the color change was recorded using the Vita Classical, Bleachedguide (ΔSGU) and Easyshade spectrophotometer (ΔE*) color scales before, during and after 30 days of the end of each treatment. The absolute risk and intensity of TS were assessed by the McNemar and Wilcoxon Signed Rank tests, respectively (α = 0.05), the color change was assessed by Wilcoxon Signed Rank (ΔSGU) and t-test for paired data (ΔE*) (α = 0.05). In the SRs (3-6) were searched for specific terms about the topic on databases and grey literature. The risk of bias was assessed using the Cochrane Collaboration tool. Meta-analysis were conducted for color change (ΔE*, ΔSGU), risk and intensity of TS using random effects model. Heterogeneity was assessed with the Cochran Q test and the I2 statistic. The quality of evidence (GRADE) was evaluated in the studies (3) and (5). Results: In the study (1), there were no differences between groups in color, risk and intensity of SD (p > 0.05); in the study (2) differences were observed only in the reduction the intensity of TS for the group with desensitizing agent in the first 24 hours (p < 0.01). In the SRs after the search of the studies, there were 21 (3), 28 (4), 11 (5), 185 (6) RCTs. In SR (3) there were no differences in color and TS (p > 0.05), and the quality of evidence was graded as moderate for ΔE* and risk of TS, and very low and low for ΔSGU and intensity of TS, respectively. In MTC SR (4), there were no differences in color without the use of light or with different light sources used. In SR (5) there was no difference in color in the combined vs. in-office bleaching (p > 0.05), and no data were available to assess the risk and intensity of TS; in combined vs. at-home bleaching no differences were observed for ΔE*, ΔSGU and risk of TS; however, lower intensity of TS was detected in the sole at-home bleaching with a standardized mean difference of 0.86 (95% CI, 0.31-1.41); and the quality of evidence was graded as moderate for color change in ΔE*, and low or very low for the other analysis. In the SR (6) in the CONSORT classification of the studies, the general mean was 16.7 ± 5.4 points (out of 32 points in total) and only 7.6% were judged as low risk of bias. Conclusions: The incorporation of the desensitizing agents in the bleaching gels used in this study did not affect the color and did not reduce the TS in the at-home bleaching (1), but it decreased the intensity of TS in the in-office bleaching (2). The use of light activation in the in-office bleaching did not improve color or affect TS regardless of the concentration of hydrogen peroxide used (3) and also did not affect color in the study (4). In combined vs. isolated bleaching (5), low intensity of TS was found in sole at-home bleaching. And in the study (6) it was concluded that adherence to CONSORT in RCTs of different bleaching techniques is low and with high risk of bias.

published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning

<p>During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken’s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased. During bleaching substances dissolve from the pulp and the amount of COD in the wastewater increase. To keep the efficiency of chemical and biological oxygen demand (COD, BOD) removal, the aerated lagoon is supplied by liquid oxygen. In November the same year a new pre-step including a pre-aeration, carrier and selector step was added to the existing wastewater plant. The COD-loading to the lagoon decreased and the supply of liquid oxygen was reduced.</p><p>This master thesis has been carried out at SCA Graphic Research AB, Sundsvall. The aim was to chemically characterize the wastewater with focus on the composition of carbohydrates, lignin and extractives and its influence on the biodegradability. Measurements have been carried out on total samples, suspended solids, colloidal and dissolved substances using GF/A and ultra filtration. Measurements were performed on process water from the bleaching plant and on water during the wastewater treatment process. The results show that the chemical composition of dissolved substances has a larger impact on the biodegradability than the total amount of COD. A large amount of lignin will make the wastewater harder to degrade. Suspended solids have lower biodegradability compared to the dissolved fraction. Analyzes of suspended material from the bleaching plant show a relative composition of around 41 % lignin. Analyzes done before on the dissolved fraction show a composition of 29 %. It seems that a larger amount of lignin is represented in suspended solids compared to the dissolved fraction. This can explain the low biodegradability, combined with the theory that the suspended solids are less accessible for the microorganisms. To reduce the outgoing COD the incoming flow of dissolved lignin and suspended solids to the active sludge plant has to decrease. COD in the outgoing wastewater to the recipient consists of around 90 % lignin. Extractives as saturated fatty acids, palmitic and stearic acid plus lignans (which is interpreted as a byproduct from lignin degradation) do not degrade remarkable during wastewater treatment. Flocculation of COD is one way to reduce the discharge to the recipient. Addition of 2,6 g/l PAX-18 (a high charged aluminum complex) to the wastewater from the bleaching plant gives a reduction of 40 % COD and 50 % lignin in laboratory scale and it is recommended to study further. Time related studies of BOD show that the microorganisms need five days to degrade organic material and the hydraulic retention time in the aerated lagoon has to be guaranteed.</p> / <p>Vid massa- och pappersframställning åtgår stora mängder vatten. Det processberörda avloppsvattnet innehåller mycket föroreningar varför det måste renas innan det släpps ut till recipienten. I mars 2004 startades ett nytt väteperoxidblekeri vid SCA Graphic Sundsvall AB, Ortvikens pappersbruk varvid produktionen av blekt termomekanisk massa ökade och den biologiska reningen belastades hårdare. Blekning löser ut vedämnen från massan och bidrar således till ökad mängd syreförbrukande ämnen i avloppet. För att upprätthålla reduktionen av syreförbrukande ämnen (COD, BOD) tillförs ren syrgas till den luftade dammen. I november samma år utökades den externa reningsanläggningen med ett biologiskt försteg, en s.k. multibioanläggning bestående av ett frisimmarsteg, ett bärarsteg samt ett selektorsteg. COD-belastningen in till den luftade dammen minskade och tillförseln av ren syrgas kunde reduceras.</p><p>Examensarbetet har utförts vid SCA Graphic Research AB, Sundsvall med syftet att kemiskt karaktärisera avloppsvattnets sammansättning av kolhydrater, lignin och extraktivämnen och dess inverkan på vattnets grad av biologisk nedbrytbarhet. Analyser har gjorts på totalprov, suspenderande ämnen samt kolloidalt och löst material via fraktionering med hjälp av GF/A- och ultrafiltrering. Analyser gjordes dels på processvatten från blekerierna och dels på avloppsvatten under reningsprocessen. Resultaten visar att den kemiska sammansättningen hos löst material har större inverkan på avloppsvattnets grad av nedbrytbarhet än den absoluta halten av syreförbrukande ämnen. En hög andel lignin ger ett mer svårnedbrytbart vatten. Suspenderat material är vidare mer svårnedbrytbart än de lösta fraktionerna. Analys av suspenderande substans hos blekpressat visar att andelen lignin är omkring 41 % medan arkiverade analysresultat på den lösta fasen visar ett innehåll på omkring 29 %. Det tyder alltså på en betydligt högre andel lignin i den partikulära fasen jämfört med den lösta, vilket i kombination med att materialet inte är lika lättillgängligt för mikroorganismerna kan förklara den låga bionedbrytbarheten. Om COD-utsläppet ska minskas bör inkommande flöde av löst lignin och suspenderande substans till den biologiska reningen reduceras. COD-halten i utgående avloppsvatten till recipienten utgörs av omkring 90 % lignin. De extraktivämnen som inte bryts ned är mättade fettsyror, exempelvis palmitin- och stearinsyra samt lignan, vilket antas bildas som restprodukt vid degradering av lignin. Flockning av syreförbrukande ämnen är ett sätt att gå till väga för att minska utsläppet av dessa till recipienten. Genom tillsats av 2,6 g/l PAX-18 (ett högladdat aluminiumkomplex) till blekeriavloppet kunde 40 % COD och 50 % lignin reduceras. Flockningsförsöket är gjort i laboratorieskala vid rumstemperatur och ytterligare utvärdering rekommenderas. Tidsstudier av BOD visar att mikroorganismerna behöver fem dagars uppehållstid för att hinna bryta ned organiskt material i avloppsvattnet, varför omloppstiden i den luftade lagunen inte bör understiga denna tidsrymd.</p>

<p>Rural people around the 4 km2 Orathupalayam Dam in southern India live in one of India’s most polluted areas. The people were once restricted mainly by scarcity of water but today they cannot drink their well water or cultivate their soil. The dam, created to store floodwater from the Noyyal River, also stores effluent water from the more than 700 dyeing and bleaching industries situated in the town of Tiruppur, 20 km upstream. Although most industries have treatment plants they do not treat total dissolved solids (TDS) and thus NaCl becomes one of the major components of the effluent. 75 to 100 million litres of effluents are released every day.</p><p>Through water sampling in open and bore wells, and with the help of GPS, ArcView and Surfer it could be concluded that high TDS levels and concentrations of Cl-, Ca2+, Mg2+ and Na+ were associated with the dam. A definite spatial pattern of the spreading of polluted water could be determined. Water from the dam was fed to the ground water all around the dam and also affected the groundwater more than 4 km to the southeast. Soil samples and interviews with farmers made it clear that land irrigated with dam water or affected well water soon became uncultivable. The water destroyed the soil structure and seeds did not germinate after irrigation with polluted water.</p><p>Through interviews it could be concluded that the local people around the dam paid a large part of the externalities of the polluting activities of the textile industries in terms of negative health effects and lost agricultural land, water resources, fishing and working opportunities. These problems have mostly been caused by the high salt concentration in the effluents but it is unclear to what extent other substances have caused or might cause harmful effects to the environment, people and animals.</p>

Ce travail de thèse a été consacré au développement d’un système multicouche constitué de nanoparticules dopées par des ions terres rares (le cœur), entourées d’une première couche cristalline non dopée, permettant de préserver les propriétés optiques du cœur. Une coquille de silice mésoporeuse est ensuite déposée, permettant l’incorporation d’un photosensibilisateur (ZnPc) via les pores de la couche de silice pour une application thérapeutique : la photothérapie dynamique. Différentes matrices ont été étudiées à savoir Y2O3, KY3F10 et NaYF4. Ces matrices ont été codopées Yb3+/Er3+ afin d’obtenir des émissions dans le visible sous l’effet d’une excitation infrarouge (upconversion), le but ultime étant d’exciter le ZnPc in situ. Chacune des matrices a été caractérisée d’un point de vue structural et morphologique dans une première partie, et d’un point de vue spectroscopique dans une deuxième partie. La structure cœur-coquille cristalline renforce l’émission rouge issue du niveau 4F9/2 de l’Er, effet déduit de l’analyse des spectres et de la dynamique de luminescence.La détection de l’oxygène singulet a été réalisée par le protocole de « bleaching » en présence ou pas du ZnPc en évaluant l’intensité de fluorescence de l’ABDA. / This work has been dedicated to the development of a multistep system composed by rare earths doped nanoparticles (core), enclosed by a first undoped crystalline layer (core-shell), serving as protection of the optical properties of the core. Within a shell of mesoporous silica allowing the loading of the photosensitizer (ZnPc) via the pores of the shell of silica for a therapeutic application: the photodynamic therapy. Various lattices were studied namely Y2O3, KY3F10 and NaYF4. These lattices were codoped with Yb3+ and Er3+ ions to obtain emissions in the visible under an infrared excitation (up conversion), the ultimate purpose being to excite in situ ZnPc. Each of these lattices was characterized from a structural and morphological point of view in the first part and, in the second part, spectroscopic studies are developed. The core-shell enhances the red emission stemming from the level 4F9/2 of Er, effect deduced from the analysis of spectra and the dynamics of luminescence. The detection of the singlet oxygen was realized in vitro by the study of the bleaching of ABDA fluorescence. The comparison of the results for nanoparticles loaded with ZnPc and unloaded ones allows demonstrating the generation of singlet oxygen by exciting in the infrared region of the spectra thanks to the efficient upconversion processes occurring in the rare earth doped materials.

Objetivos: Estudos clínicos longitudinais que acompanham os pacientes por longos períodos não são muito comuns na literatura, ainda mais quando associados a grandes amostras (veio do fim do resumo). Por isso, o objetivo do trabalho foi determinar a eficiência, estabilidade de cor e sensibilidade dental, trans e pós operatória, dentro de um período de 365 dias, de quatro protocolos de clareamento em consultório. Material e Métodos: Foi realizado um estudo clínico randomizado, cego (para os pacientes), composto por 120 sujeitos (n=30). A amostra foi formada por pacientes adultos, sem distinção de gênero e etnia, e idade superior a 18 anos que foram selecionados por meio de avaliação clínica na qual foi verificada a cor dos dentes, a condição de higiene oral e a presença de restaurações e/ou próteses nas regiões em que os procedimentos seriam realizados. Todos os sujeitos foram submetidos a uma sessão de clareamento de acordo com as instruções do fabricante e obedecendo a aplicação ou não da luz, para os clareadores baseados no sistema Foto-Fenton (havia faltado citar nos métodos do resumo), e qual o seu tipo: Zoom Advanced Power, peróxido de hidrogênio (PH) 25% - Zoom! + luz UVA (Phillips Oral Healthcare); Zoom Whitespeed, PH 25% - Zoom! + luz Whitespeed (Phillips Oral Healthcare); Zoom sem luz, PH 25% - Zoom! (Phillips Oral Healthcare). Boost, PH 38% - Opalescence Xtra Boost (Ultradent). As alterações de cor foram avaliadas utilizando as escalas Vita Classical e Vita Bleachedguide 3D Master e o Espectrofotômetro Vita-Easyshade. As medições foram feitas em incisivos centrais e caninos uperiores antes, imediatamente e 7, 14, 30, 180 e 365 dias após o tratamento. Os dados foram analisados estatisticamente por meio do software Statistica 8.0 (StatSoft - Tulsa, OK) através da análise de variância (ANOVA) para medidas repetidas na avaliação das médias e as comparações foram realizadas através de contrastes (Tukey). Resultados: Para a escala Vita Classical, Zoom AP e WS foram semelhantes entre si porém diferentes de Opalescence e Zoom sem luz, exceto para a avaliação de 30 dias (caninos) e 365 dias (incisivos) onde o Zoom WS demonstrou dados semelhantes ao Opalescence e Zoom sem luz Já para a escala Vita Bleached, Zoom AP e WS foram semelhantes entre si, porém diferentes de Opalescence e Zoom sem luz, exceto para as avaliações de 30 e 180 dias onde o Zoom WS demonstrou dados semelhantes ao Opalescence e Zoom sem luz (caninos). Para dentes incisivos, os achados foram semelhantes, exceto que houve diferença entre o Zoom AP e WS e as semelhanças entre Zoom WS, Opalescence e Zoom sem luz foram encontradas nas avaliações de 180 e 365 dias. Na avalição com o espectrofotômetro Vita Easyshade Zoom AP e WS foram semelhantes entre si e diferentes do Opalescence que, por sua vez, foi diferente do Zoom sem luz, exceto para as avaliações de 7, 14 e 30 dias (caninos). Para incisivos, Zoom AP e WS foram semelhantes entre si e diferentes de Opalescence e Zoom sem luz, exceto para a avaliação de 14 dias onde o Zoom AP foi diferente do Zoom WS. Por fim, a sensibilidade apresentou um aumento nos seus valores na avaliação imediatamente após o clareamento, com uma redução na avalição de 7 dias, para todos os grupos que ainda apresentaram valores de sensibilidade semelhantes em todos os períodos de avaliação. Conclusão: O acompanhamento até 365 dias demonstrou a eficiência dos protocolos de clareamento analisados uma vez que nenhum deles recidivou para os tons iniciais, demonstrando a durabilidade dos procedimentos. Os dois grupos com os clareadores Foto-Fenton obtiveram maior efeito clareador (substituiu desempenho, tinha ficado vago), exceto nas seguintes avaliações: Vita Classical, 30 dias (caninos) e 365 dias (incisivos) e Vita Bleached, 30 e 180 dias (caninos) e 180 e 365 dias (incisivos). Observou-se uma estabilização da cor após sete dias em todos os grupos. A sensibilidade pós operatória foi mais intensa nos primeiros 7 dias e nenhum paciente relatou sensibilidade a partir da avaliação de 14 dias. / Objectives: Longitudinal clinical studies that follow patients for long periods are not very common in the literature, especially when associated with large samples. The objective of this study was to determinate the efficacy, color stability and sensitivity within a 365 day period of four in-office bleaching protocols. Methods: A randomized clinical trial, blinded (for patients), composed of 120 subjects (n=30) was conducted. The sample consisted of adult patients, without gender and ethnic distinction, with age superior than 18 years old that were selected through clinical evaluation in which was verified the color of teeth, the condition of oral hygiene and the presence of restorations and/or prostheses in the areas where the procedures would be carried out. All subjects were submitted to a session of bleaching according to the manufacturer\'s instructions: Zoom Advanced Power, 25% hydrogen peroxide (HP) - Zoom! + UVA light (Phillips Oral Healthcare); Zoom Whitespeed, 25% HP - Zoom! + Whitespeed light (Phillips Oral Healthcare); Zoom without light, 25% HP - Zoom! (Phillips Oral Healthcare). Boost, 38% HP - Opalescence Xtra Boost (Ultradent). Color changes were evaluated using Vita Classical and Vita Bleachedguide 3D Master shade guides and Vita-Easyshade spectrophotometer. Measurements were made on the superior central incisive and canines before, immediately and 7, 14, 30, 180 and 365 days after the treatment. Statistical analysis of the data were made with the software Statistica 8.0 (StatSoft - Tulsa, OK) through the analysis of variance (ANOVA) for repeated measures in the mean evaluation and comparisons were made by using contrasts (Tukey). Results: For the Vita Classical shade guide, Zoom AP and WS were similar but different from Opalescence and Zoom without light except for the 30 day (canines) and 365 days evaluations (incisives) where the Zoom WS showed similar data to Opalescence and Zoom without light. As for the Vita Bleached shade guide, Zoom AP and WS were similar, but different from Opalescence and Zoom without light, except for the 30 and 180 days evaluation where Zoom WS showed similar data to Opalescence and Zoom without light (canines). For incisives, the findings were similar, except that there were differences between Zoom AP and WS and the similarities between Zoom WS, Opalescence and Zoom without light were found in the 180 and 365 days evaluations. For the evaluation with Vita Easyshade spectrophotometer, Zoom AP and WS were similar and different from Opalescence which was different from Zoom without light, except for the 7, 14 and 30 days evaluation (canines). For incisives, Zoom AP and WS were similar and different from Opalescence and Zoom without light, except for the 14 days evaluation where Zoom AP was different from Zoom WS. Finally, the sensitivity showed an increase in their values for the immediately after bleaching evaluation, with a reduction in the 7 days evaluation for all groups that still had similar sensitivity values in all evaluation periods. Conclusion: The follow-up to 365 days demonstrated the efficiency of the analyzed bleaching protocols since none relapsed to the initial shades, demonstrating the durability of the procedures. The two groups with the Photo-Fenton bleaching systems performed better, except for the following evaluations: Vita Classical, 30 days (canines) and 365 days (incisives) and Vita Bleached, 30 and 180 days (canines) and 180 and 365 days (incisives). There was a color stabilization after seven days in all groups. Postoperative sensitivity was more intense in the first 7 days and no patient reported sensitivity since the 14 days evaluation.

O presente estudo teve por objetivo avaliar a eficiência da extração de lignina de cavacos da madeira de Eucalyptus grandis x Eucalyptus urophylla a partir de pré-tratamentos com xilenosulfonato de sódio (SXS), bem como determinar as condições ótimas destes, com intuito de aumentar a eficiência dos processos de polpação e branqueamento, através da redução da necessidade de reagentes. Primeiramente procedeu-se a caracterização física, química e morfológica da madeira. Na sequência os cavacos foram submetidos à pré-tratamentos a partir da combinação dos fatores: tempo (1, 3, 6, 9 e 12 h), concentração de SXS (0, 10, 20 e 30 %) e temperatura (110, 120 e 130 ºC). Após os pré-tratamentos determinaram-se os parâmetros de rendimento e teor de lignina remanescente nos cavacos, a partir dos quais obtiveram-se os pontos ótimos referentes a cada fator, para o máximo rendimento e extração de lignina. De posse dos pontos ótimos para cada parâmetro, esses foram replicados para obtenção de cavacos pré-tratados que foram utilizados nas curvas de cozimento pelo processo kraft de polpação com e sem a aplicação de antraquinona e comparados a cavacos normais. A partir das curvas de cozimento determinou-se a carga alcalina necessária para obtenção de polpa com número kappa 15 ± 0,5. Na sequência as polpas obtidas foram branqueadas, refinadas e avaliadas quanto as suas características físico-mecânicas. Os resultados da caracterização física, química e morfológica demonstraram que a madeira em questão apresenta valores consoantes com os citados na literatura. Os pré-tratamentos com SXS foram eficientes na extração da lignina. O pré-tratamento que proporcionou o maior rendimento foi 1 h, 0 %, 117,5 ºC; e a maior extração de lignina foi com 12 h, 30 %, 130 ºC, removendo 39,60 % desta. Com base nas curvas de cozimento observou-se que os valores de rendimento da polpa obtida a partir dos cavacos pré-tratados com SXS são muito inferiores aos cavacos normais, porém em contrapartida apresentaram alto grau de deslignificação, sendo possível obter polpa de mesmo número kappa com cargas de álcali ativo consideravelmente menores que para cavacos normais, desta forma aumentando a eficiência do processo de polpação. Para polpa com mesmo número kappa (15 ± 0,5) a carga alcalina necessária foi 34,8 e 37,6 % menor para os cavacos pré-tratados com SXS, sem e com antraquinona, respectivamente, quando comparado com os cavacos normais. As polpas obtidas dos cavacos pré-tratados apresentaram maior eficiência na pré-deslignificação com oxigênio e maior branqueabilidade. Em relação aos testes físicos e mecânicos, as polpas obtidas com o pré-tratamento com SXS apresentaram bom desempenho nas propriedades físicas, porém nas mecânicas foram inferiores. De maneira geral, o pré-tratamento dos cavacos da madeira de E. grandis x E. urophylla com SXS foi eficaz na extração de lignina, reduzindo a necessidade de reagentes químicos nas etapas de polpação e branqueamento, aumentando a eficiência de ambas. Assim recomenda-se o pré-tratamento de 12 h, 30 % SXS, 130 ºC para remoção da maior quantidade de lignina dos cavacos, de maneira a otimizar o processo de polpação kraft, reduzindo a necessidade de reagentes. / The present study aimed evaluate the efficiency of lignin extraction from wood chips of Eucalyptus grandis x Eucalyptus urophylla from pretreatments with sodium xylenesulphonate (SXS), and determine the optimum conditions of these, in order to increase the efficiency of the pulping and bleaching processes, by reducing the necessity of reagents. First of all proceeded the physical, chemical and morphological characterization of wood. After the chips were submitted to pretreatments from the combination of factors: time (1, 3, 6, 9 and 12 h), concentration of SXS (0, 10, 20 and 30 %) and temperature (110, 120, and 130 °C). After the pretreatments were determined the yield and the level of remaining lignin in the chips, from which was obtained the optimal points for each factor for maximum yield and lignin extraction. With the optimum points for each parameter, these were replicated to obtain pretreated wood chips that were used in the cooking curves from kraft pulping process, and compared with normal chips, both with and without anthraquinone. From the cooking curves were determined the alkaline charge required to obtain pulp with a kappa number of 15 ± 0.5, which was reproduced for evaluation the characteristics of the pulp obtained from the wood chips with and without pretreatment. Later these pulps were bleached, refined and evaluated for their physical and mechanical characteristics. The results of physical, chemical and morphological characterization showed that the wood in question has consonant with the values reported in the literature. The pretreatments with SXS were efficient to lignin extracting. The pretreatment that provided the highest yield was 1 h, 0 %, 117.5 °C; and the highest extraction of lignin was 12 h, 30 %, 130 °C, removing 39,60 % thereof. Based on the cooking curves was observed that the values obtained for yield of pulp from pretreated wood chips with SXS were much lower than normal chips, but in other hand showed a high delignification degree, being possible obtain pulp with the same kappa number with active alkali charges considerably smaller than for normal chips, thereby increasing the efficiency of the pulping process. For pulp with the same kappa number (15 ± 0.5) the alkaline charge required was 34.8 and 37.6 % lower for pretreated wood chips with SXS, without and with anthraquinone, respectively, when compared with normal chips. The pulps obtained from the pretreated wood chips showed higher efficiency in the pre-delignification with oxygen and higher bleachability. For physical and mechanical tests, the pulps obtained by pretreatment with SXS presented good performance in physical properties, but were lower in mechanical tests. In general way, the pretreatment of the wood chips of E. grandis x E. urophylla with SXS was efficient in the lignin extraction, reducing the necessity of the chemicals in pulping and bleaching stages, increasing the efficiency of both. Thus it is recommended pretreatment of 12 h, 30 % SXS 130 °C to remove as much of the lignin from the chips, in order to optimize the kraft pulping process, reducing the need for reagents.

Este estudo teve como objetivos: 01.Avaliar ex vivo o efeito de diferentes sistemas clareadores na microdureza dentinária em dentes bovinos submetidos ao clareamento dental interno. 02.Avaliar ex vivo o efeito de diferentes sistemas clareadores na morfologia superficial da dentina bovina. Fragmentos de 4 x 4mm, contendo esmalte e dentina, foram obtidos de coroas de incisivos bovinos extraídos. Os espécimes foram submetidos ao clareamento dental interno com peróxido de hidrogênio a 35% e peróxido de carbamida a 37% utilizando sistemas convencionais (Opalescence Endo® and Whiteness Super Endo®) e fotoativados (Opalescence Xtra® and Whiteness HP Maxx®). Os controles foram tratados com perborato de sódio misturado com peróxido de hidrogênio a 10% ou nenhum tratamento foi realizado. A microdureza dentinária foi mensurada antes e após os tratamentos clareadores, e os valores de dureza Knoop (KHN) foram submetidos à análise estatística (two-way ANOVA, Tukey\'s port-test). Os espécimes foram observados e fotografados sob microscópio eletrônico de varredura e avaliados com relação às alterações morfológicas da superfície da dentina. Houve uma redução significante na microdureza dentinária para todos os grupos testados quando comparados aos grupos controles. Opalescence Xtra® (-11.36 ± 8.14 KHN), Opalescence Endo® (-13.71 ± 8.02 KHN), Whiteness HP Maxx® (-15.18 ± 9.58 KHN) e Whiteness Super Endo® (-16.97 ± 6.55 KHN) foram semelhantes estatisticamente. O grupo do perborato de sódio misturado com peróxido de hidrogênio 10% (2.10 ± 8.58 KHN) e o grupo sem tratamento clareador (-2.71 ± 2.40 KHN) também foram estatisticamente semelhantes entre si. Ocorreu uma grande variação no padrão de alterações da morfologia superficial da dentina com os sistemas clareadores utilizados. Todos os produtos testados apresentaram redução significativa da microdureza dentinária, exceto o grupo de perborato de sódio misturado com peróxido de hidrogênio a 10%. Ambos, pH e oxidação do peróxido de hidrogênio apresentam o papel de alterar a estrutura da dentina durante o clareamento interno. A utilização de produtos alcalinos com um tempo reduzido de aplicação (técnicas fotoativadas) pode diminuir as alterações morfológicas na dentina. / The aim of this study was: 01. To evaluate in vitro the effect of different in-office bleaching systems on the surface morphology of bovine dentin. 02. To evaluate ex vivo the effect of different bleaching systems on the microhardness of bovine dentine. Tooth fragments measuring 4 x 4mm, containing enamel and dentin, were obtained from the crowns of extracted bovine incisors. Samples were submitted to simulated intracoronal bleaching techniques with 35% hydrogen peroxide and 37% carbamide peroxide using conventional (Opalescence Endo® and Whiteness Super Endo®) and light activated systems (Opalescence Xtra® and Whiteness HP Maxx®). Controls were treated either with sodium perborate mixed with 10% hydrogen peroxide or no bleaching agent. Dentine microhardness values were measured before and after bleaching procedures, recorded as KHN (Knoop Hardness Number), and the differences between them analyzed (two-way ANOVA, Tukey\'s port-test). The samples were observed under SEM and the recorded images were evaluated for topographic alterations. Significant reductions of dentine microhardness were observed for all treatments when compared to the control groups. Opalescence Xtra® (-11.36 ± 8.14 KHN), Opalescence Endo® (-13.71 ± 8.02 KHN), Whiteness HP Maxx® (-15.18 ± 9.58 KHN) and Whiteness Super Endo® (- 16.97 ± 6.55 KHN) presented similar differences. The walking bleach technique (2.10 ± 8.58 KHN) and the untreated groups (-2.71 ± 2.40 KHN) were statistically alike.The ultrastructural alterations of dentin observed in this study varied greatly between groups, according to the products used. Apparently, higher pH products associated to in-office techniques yielded to better maintenance of dentin ultrastructure. The in-office products tested in the present study caused a significant reduction in dentine microhardness. The walking bleach technique did not affect dentine microhardness. Both low pH and hydrogen peroxide oxidation play a role in altering the ultrastructure of dentin during internal dental bleaching. The use of alkaline products with reduced time of application (in-office techniques) may decrease such morphological alterations.