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During the preparation of fixed prosthesis (including individual bridges and crowns) it is important to select the materials that have the best features and properties to predict a successful clinical treatment. The objective of this study was to determine if the chemical and structural characteristics could cause to increase the fracture resistance, we used four bis-acryl resins Luxatemp, Protemp, Structur and Telio. Three-points bending by Flexural test were performed in ten bars and they were carried out to compare with Anova test. In addition, the bis-acryl resins were analyzed by scanning electron microscopy, to analyze microstructure and morphology and the molecular structure were performed by Infrared Spectroscopy through Attenuated Total Reflectance. A higher flexural strength was found in Luxatemp and Structur with, no significant differences between this study groups. Regarding Protemp and Telio, these study groups showed a lower flexural strength when were compared with Luxatemp and Structur. These results corroborate SEM and ATR analysis because Luxatemp sample showed a regular size particle on the surface and chemically presents a long cross-linkage polymer chain. The presence of CO3, SiO2 and N-H groups as a fillers particle interacting with OH groups cause a higher flexural strength compared with another groups.

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The search for new analytical methods is a latent reality in the so-called green analytical chemistry area, which aims at correlating analytical demands to environmental issues. Among the approaches used, it is possible to highlight green solvents as substitutes to the dangerous and conventional organic solvents as the most prominent alternative for this purpose. In the last few years, the amount of research focused on the usage of deep eutectic solvents (DESs) has been growing as an alternative to these issues. Thus, this work aimed to investigate the main physical-chemical and ecotoxical properties of seven different DESs. The results showed that DESs' evaluated properties are influenced by the chemical structure of their precursors, which may regulate DESs' viscosity, superficial tension, and antagonistic action against vegetable tissues and microbial cells. The constatations pointed here introduce a new perspective about the conscious usage of DESs on a green analytical point of view.

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The aim of this study was to measure the fluoride (F) and silver (Ag) ion concentration and the pH, over time, of 2 solutions of 38% silver diamine fluoride (SDF) produced in Argentina. The brand Fluorsilver® was established as Group 1 (G1) (Densell), and the brand FAgamin® (Tedequim) as Group 2 (G2), each with two different lots. The following were determined at time 0 (t0) and 30 days after opening (t30): a) fluoride concentration (w/v) by visible spectrophotometry b) Ag content (w/v) by atomic absorption spectrophotometry c) pH. Results: The data in the freshly opened bottles were for G1 lot1/lot2: a) 0.96/1, b) 8.3/7.8, c).11.5/11.3; G2 lot1/lot2: a) 11.5/9.9, b) 39/39, c) 7/6,9; and after 30 days, G1 lot1/lot2: a) 0.85/0.81, b) 7.2/8.2, c) 11.3/11.6; G2 lot1/lot2: a) 9.35/8.43, b) 38/38, c) 7.6/7.6. Conclusion In relation to the expected values (5.0-5.9% fluoride and 24.4-28.8% silver), the average concentration of fluoride and silver ions was lower for G1, but higher for G2. The pH was alkaline for G1 and neutral for G2. Over the 30 days, the content of fluoride and silver tended to decrease.

El objetivo de este estudio fue medir las concentraciones de iones de fluoruro (F) y plata (Ag) y el pH, de 2 soluciones de diamino fluoruro de plata (SDF) al 38% producidas en Argentina. Se estableció como Grupo 1 (G1) la marca Fluorsilver® (Densell), y FAgamin® (Tedequim) como Grupo 2 (G2), cada uno con dos lotes diferentes. Se determinó: a) la concentración de fluoruro (p/v) por espectrofotometría visible, b) el contenido de Ag (p/v) por espectrofotometría de absorción atómica y c) el pH, y fue medido en un tiempo 0 (t0) y 30 días después de la apertura del frasco (t30). Resultado: En tiempo 0 para G1 lote1/lote2 fue: a) 0,96/1, b) 8,3/7,8 c).11,5/11,3 y G2 lote1/lote2: a) 11,5/9,9, b) 39/39, c) 7/6,9. A los 30 días G1 lote1/lote2: a) 0,85/0,81, b) 7,2/8,2, c) 11,3/11,6 y G2 lote1/lote2: a) 9,35/8,43, b) 38/38, c) 7,6/7,6. La concentración de iones de fluoruro y plata para G1 fue menor en relación a los valores esperados (5,0-5,9% de fluoruro y 24,4- 28.8% plata), sin embargo G2 obtuvo valores más altos. G1 muestra resultados de pH alcalino y G2 neutro. A lo largo de los 30 días, el contenido de fluoruro y plata tiende a disminuir.

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ABSTRACT The aim of this study was to measure the fluoride (F) and silver (Ag) ion concentration and the pH, over time, of 2 solutions of 38% silver diamine fluoride (SDF) produced in Argentina. The brand Fluorsilver® was established as Group 1 (G1) (Densell), and the brand FAgamin® (Tedequim) as Group 2 (G2), each with two different lots. The following were determined at time 0 (t0) and 30 days after opening (t30): a) fluoride concentration (w/v) by visible spectrophotometry b) Ag content (w/v) by atomic absorption spectrophotometry c) pH. Results: The data in the freshly opened bottles were for G1 lot1/lot2: a) 0.96/1, b) 8.3/7.8, c).11.5/11.3; G2 lot1/lot2: a) 11.5/9.9, b) 39/39, c) 7/6,9; and after 30 days, G1 lot1/lot2: a) 0.85/0.81, b) 7.2/8.2, c) 11.3/11.6; G2 lot1/lot2: a) 9.35/8.43, b) 38/38, c) 7.6/7.6. Conclusion In relation to the expected values (5.0-5.9% fluoride and 24.4-28.8% silver), the average concentration of fluoride and silver ions was lower for G1, but higher for G2. The pH was alkaline for G1 and neutral for G2. Over the 30 days, the content of fluoride and silver tended to decrease.

RESUMEN El objetivo de este estudio fue medir las concentraciones de iones de fluoruro (F) y plata (Ag) y el pH, de 2 soluciones de diamino fluoruro de plata (SDF) al 38% producidas en Argentina. Se estableció como Grupo 1 (G1) la marca Fluorsilver® (Densell), y FAgamin® (Tedequim) como Grupo 2 (G2), cada uno con dos lotes diferentes. Se determinó: a) la concentración de fluoruro (p/v) por espectrofotometría visible, b) el contenido de Ag (p/v) por espectrofotometría de absorción atómica y c) el pH, y fue medido en un tiempo 0 (t0) y 30 días después de la apertura del frasco (t30). Resultado: En tiempo 0 para G1 lote1/lote2 fue: a) 0,96/1, b) 8,3/7,8 c).11,5/11,3 y G2 lote1/lote2: a) 11,5/9,9, b) 39/39, c) 7/6,9. A los 30 días G1 lote1/lote2: a) 0,85/0,81, b) 7,2/8,2, c) 11,3/11,6 y G2 lote1/lote2: a) 9,35/8,43, b) 38/38, c) 7,6/7,6. La concentración de iones de fluoruro y plata para G1 fue menor en relación a los valores esperados (5,0-5,9% de fluoruro y 24,4- 28.8% plata), sin embargo G2 obtuvo valores más altos. G1 muestra resultados de pH alcalino y G2 neutro. A lo largo de los 30 días, el contenido de fluoruro y plata tiende a disminuir.

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Calcium phosphate cements have the advantage that they can be prepared as a paste that sets in a few minutes and can be easily adapted to the shape of the bone defect, which facilitates its clinical application. In this research, six formulations of brushite (dicalcium phosphate dihydrated) cement were obtained and the effect of the addition of sodium alginate was analyzed, such as its capacity as a tetracycline release system. The samples that contain sodium alginate set in 4 or 5 min and showed a high percentage of injectability (93%). The cements exhibit compression resistance values between 1.6 and 2.6 MPa. The drug was released in a range between 12.6 and 13.2% after 7 days. The antimicrobial activity of all the cements containing antibiotics was proven. All samples reached values of cell viability above 70 percent. We also observed that the addition of the sodium alginate and tetracycline improved the cell viability.

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OBJECTIVE: To propose a biofunctionalized prosthetic abutment by analyzing physico-chemical and morphological properties, simvastatin (SIM) release, and biocompatibility of titanium (Ti) disks coated with poly(lactic-co-glycolic) acid (PLGA) incorporating SIM. METHODS: Titanium disks (8 × 3 mm) were distributed into four groups: Ti: pure Ti; Ti + PLGA: Ti coated with PLGA; Ti + PLGA + SIM6%: Ti + PLGA with 6% SIM; and Ti + PLGA + SIM0.6%: Ti + PLGA incorporating 0.6% SIM. PLGA was prepared through chloroform evaporation technique. After complete dissolution of PLGA, SIM was diluted in the solution. Ti + PLGA, Ti + PLGA + SIM6%, and Ti + PLGA + SIM0.6% were dip coated with PLGA and PLGA + SIM, respectively. Samples were sterilized by ethylene oxide. For SIM release assay, disks were submerged in PBS, pH 7.4, 37°C, 30 rpm up to 600 hours. At different time intervals, SIM was quantified by spectrophotometry (238 nm). For characterization of the biomaterial components, it was performed Fourier-transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy (SEM), optical profilometry, and atomic force microscopy. Biocompatibility analyses were performed by MTS colorimetric assay on murine fibroblasts L929, human gingival fibroblasts (HGFs), and stem cells from human exfoliated deciduous teeth (SHEDs). Absorbance was measured at 490 nm, and percentages of viable cells were calculated in relation to positive control (Ti). SEM images were obtained to verify cell adhesion and morphology. One-way ANOVA followed by Tukey's post hoc test was applied (P < 0.05) for statistical analyses. RESULTS: SIM release was slow and continuous, reaching about 21% of the incorporated SIM after 600 hours. Topographical analyses revealed success in coating Ti disks with PLGA incorporating SIM. Regarding biocompatibility test, Ti + PLGA + SIM0.6% showed the highest percentage of L929 viability at days 3 and 7. There was no significant difference for Ti, Ti + PLGA, and Ti + PLGA + SIM0.6% groups on cell viability of both SHEDs and HGFs at days 3 and 7. SEM corroborates that SHEDs and HGFs were able to adhere and proliferate on Ti, Ti + PLGA, and Ti + PLGA + SIM0.6% surfaces. CONCLUSION: A slow and controlled release of SIM was achieved, attributed to a diffusional mass transfer mechanism. Moreover, a homogenous coating topography was obtained. Additionally, 0.6% SIM incorporated into PLGA coating improved fibroblasts L929 viability compared to titanium or PLGA. Also, 0.6% SIM incorporated into PLGA promoted cell viability of about 100% for HGFs and approximately 150% for human mesenchymal stem cells. Therefore, this study allows to consider the use of PLGA-coated titanium incorporating SIM as a biofunctionalized abutment for dental implants.

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The physicochemical properties of a substance, such as a fuel, can vary significantly with composition. Determining these properties with ASTM standard methods is both expensive and time-consuming, which has led to a desire to use chemometric modeling as an alternative. In this study, we compare the accuracy and robustness of two chemometric models, partial least squares (PLS) regression and support vector machine (SVM) with uncertainty estimation to determine how the physicochemical properties depend on the composition. A set of hydrocarbon mixtures, including crude oil, oil, gasoline, and biofuel/biodiesel, were collected. GC-MS data were taken, and physicochemical properties were measured for these mixtures using ASTM standard methods. PLS and SVM were used to develop predictive models of the physicochemical properties. Uncertainty in the estimated property values was estimated using a bootstrapping technique. With this uncertainty estimate, it is possible to assess the trustworthiness of any prediction, which ensures that the chemometric models can be applied for general purposes. SVM was found to be generally better for predicting the physicochemical properties, although we expect that with a more comprehensive data set the performance of the PLS models can be improved. We show in this work that PLS and SVM can be used to generate a predictive model of physicochemical properties based on GC-MS data. Combined with uncertainty analysis, these models provide robust predictions that can be used for regulatory, economic, and safety purposes.

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The honey from Tiúba bees (Melipona fasciculata) is commercially important in the Brazilian state of Maranhão. However, the absence of any specific legislation for this kind of honey is an obstacle to its increased production and commercialization. Determining the microbiological and physical-chemical characteristics of different Tiúba honey can inform the elaboration of specific legislation. Thus, honey samples from two Water Catchment Areas in Maranhão (Munim and Pericumã, sample size 20 for each) were collected and submitted for microbiological analysis (total coliforms, thermotolerant coliforms, molds and yeasts, Clostridium sulfite reducers and Salmonella sp.) and physical-chemical analysis (moisture content, reducing and non-reducing sugars, insoluble and soluble solids, ash content, acidity and pH). Most of honeys sampled were suitable for human consumption, except for one sample from Pericumã. Honeys from the two water catchment areas presented differences in some physicochemical characteristics, which can be attributed to the botanic, soil and climatic diversity of the two areas. Still, these Tiúba honey samples did not fall within the Brazilian legislation for Apis mellifera honey for some of the physical-chemical characteristics, and so is not properly regulated, thus reinforcing the need for specific legislation for this type of honey.(AU)

O mel de Tiúba (Melipona fasciculata) tem importância comercial na região do estado do Maranhão, no entanto a ausência de uma legislação específica para este mel entrava a ampliação de sua produção e comercialização. Dessa forma, faz-se necessário determinar as características microbiológicas e físico-químicas de méis de Tiúba, com o objetivo de fornecer subsídios para a elaboração de uma legislação específica. Assim, amostras de méis provenientes de duas bacias hidrográficas do Maranhão (Munim n = 20, e Pericumã n = 20) foram coletadas e submetidas às análises microbiológicas (coliformes totais, coliformes termotolerantes, bolores e leveduras, Clostridium sulfito redutores e Salmonella sp.) e físico-químicas (umidade, açúcares redutores e não redutores, sólidos insolúveis e solúveis, cinzas, acidez e pH). A maioria dos méis apresentou-se adequado microbiologicamente ao consumo humano, exceto uma amostra de mel proveniente de Pericumã. Os méis provenientes das duas bacias hidrográficas apresentaram diferenças em algumas características físico-químicas, o que pode ser atribuído à diversidade botânica, edáfica (solo) e climática das duas bacias. Ainda, os méis de Tiúba não se adequaram à legislação brasileira de Apis mellifera para algumas características físico-químicas, o que não permite sua regulamentação e, assim, reforça a necessidade de legislação específica para este tipo de mel.(AU)

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The adsorption-desorption, hysteresis phenomenon, and leachability of tebuconazole were studied for Inceptisol and Histosol soils at the surface (0-10 cm) and in the subsurface (40-50 cm) of an agricultural region from Colombia by the batch-equilibrium method and mathematical approaches. The experimental Kfa and Kd (L kg-1) values (7.9-289.2) decreased with depth for the two Inceptisols and increased with depth for the Histosol due to the organic carbon content, aryl and carbonyl carbon types. Single-point and desorption isotherms depended on adsorption reversibility and suggested that tebuconazole showed hysteresis; which can be adequately evaluated with the single-point desorption isotherm and the linear model using the hysteresis index HI. The most suitable mathematical approach to estimate the adsorption isotherms of tebuconazole at the surface and in the subsurface was that considering the combination of the n-octanol-water partition coefficient, pesticide solubility, and the mass-balance concept. Tebuconazole had similar moderate mobility potential as compared with the values of other studies conducted in temperate amended and unamended soils, but the risk of the fungicide to pollute groundwater sources increased when the pesticide reached subsurface soil layers, particularly in the Inceptisols.

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ABSTRACT: The honey from Tiúba bees (Melipona fasciculata) is commercially important in the Brazilian state of Maranhão. However, the absence of any specific legislation for this kind of honey is an obstacle to its increased production and commercialization. Determining the microbiological and physical-chemical characteristics of different Tiúba honey can inform the elaboration of specific legislation. Thus, honey samples from two Water Catchment Areas in Maranhão (Munim and Pericumã, sample size 20 for each) were collected and submitted for microbiological analysis (total coliforms, thermotolerant coliforms, molds and yeasts, Clostridium sulfite reducers and Salmonella sp.) and physical-chemical analysis (moisture content, reducing and non-reducing sugars, insoluble and soluble solids, ash content, acidity and pH). Most of honeys sampled were suitable for human consumption, except for one sample from Pericumã. Honeys from the two water catchment areas presented differences in some physicochemical characteristics, which can be attributed to the botanic, soil and climatic diversity of the two areas. Still, these Tiúba honey samples did not fall within the Brazilian legislation for Apis mellifera honey for some of the physical-chemical characteristics, and so is not properly regulated, thus reinforcing the need for specific legislation for this type of honey.

RESUMO: O mel de Tiúba (Melipona fasciculata) tem importância comercial na região do estado do Maranhão, no entanto a ausência de uma legislação específica para este mel entrava a ampliação de sua produção e comercialização. Dessa forma, faz-se necessário determinar as características microbiológicas e físico-químicas de méis de Tiúba, com o objetivo de fornecer subsídios para a elaboração de uma legislação específica. Assim, amostras de méis provenientes de duas bacias hidrográficas do Maranhão (Munim n = 20, e Pericumã n = 20) foram coletadas e submetidas às análises microbiológicas (coliformes totais, coliformes termotolerantes, bolores e leveduras, Clostridium sulfito redutores e Salmonella sp.) e físico-químicas (umidade, açúcares redutores e não redutores, sólidos insolúveis e solúveis, cinzas, acidez e pH). A maioria dos méis apresentou-se adequado microbiologicamente ao consumo humano, exceto uma amostra de mel proveniente de Pericumã. Os méis provenientes das duas bacias hidrográficas apresentaram diferenças em algumas características físico-químicas, o que pode ser atribuído à diversidade botânica, edáfica (solo) e climática das duas bacias. Ainda, os méis de Tiúba não se adequaram à legislação brasileira de Apis mellifera para algumas características físico-químicas, o que não permite sua regulamentação e, assim, reforça a necessidade de legislação específica para este tipo de mel.

RESUMO

The honey from Tiúba bees (Melipona fasciculata) is commercially important in the Brazilian state of Maranhão. However, the absence of any specific legislation for this kind of honey is an obstacle to its increased production and commercialization. Determining the microbiological and physical-chemical characteristics of different Tiúba honey can inform the elaboration of specific legislation. Thus, honey samples from two Water Catchment Areas in Maranhão (Munim and Pericumã, sample size 20 for each) were collected and submitted for microbiological analysis (total coliforms, thermotolerant coliforms, molds and yeasts, Clostridium sulfite reducers and Salmonella sp.) and physical-chemical analysis (moisture content, reducing and non-reducing sugars, insoluble and soluble solids, ash content, acidity and pH). Most of honeys sampled were suitable for human consumption, except for one sample from Pericumã. Honeys from the two water catchment areas presented differences in some physicochemical characteristics, which can be attributed to the botanic, soil and climatic diversity of the two areas. Still, these Tiúba honey samples did not fall within the Brazilian legislation for Apis mellifera honey for some of the physical-chemical characteristics, and so is not properly regulated, thus reinforcing the need for specific legislation for this type of honey.

O mel de Tiúba (Melipona fasciculata) tem importância comercial na região do estado do Maranhão, no entanto a ausência de uma legislação específica para este mel entrava a ampliação de sua produção e comercialização. Dessa forma, faz-se necessário determinar as características microbiológicas e físico-químicas de méis de Tiúba, com o objetivo de fornecer subsídios para a elaboração de uma legislação específica. Assim, amostras de méis provenientes de duas bacias hidrográficas do Maranhão (Munim n = 20, e Pericumã n = 20) foram coletadas e submetidas às análises microbiológicas (coliformes totais, coliformes termotolerantes, bolores e leveduras, Clostridium sulfito redutores e Salmonella sp.) e físico-químicas (umidade, açúcares redutores e não redutores, sólidos insolúveis e solúveis, cinzas, acidez e pH). A maioria dos méis apresentou-se adequado microbiologicamente ao consumo humano, exceto uma amostra de mel proveniente de Pericumã. Os méis provenientes das duas bacias hidrográficas apresentaram diferenças em algumas características físico-químicas, o que pode ser atribuído à diversidade botânica, edáfica (solo) e climática das duas bacias. Ainda, os méis de Tiúba não se adequaram à legislação brasileira de Apis mellifera para algumas características físico-químicas, o que não permite sua regulamentação e, assim, reforça a necessidade de legislação específica para este tipo de mel.

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Abstract Physical-chemical and rheological properties of pork batters as affected by replacing pork back-fat with pre-emulsified sesame oil were investigated. Replacement of pork back-fat with pre-emulsified sesame oil, improved L* value, moisture and protein content, hardness, cohesiveness, and chewiness, declined a* value, fat content and energy, but not affect cooking yield. When used pre-emulsified sesame oil to replace pork back-fat 50%, the sample had the highest L* value and texture. According to the results of dynamic rheological, replaced pork back-fat by pre-emulsified sesame oil increased the storage modulus (G') values at 80 °C, and formed firm gel. The result of Low-field nuclear magnetic resonance (LF-NMR) shown that the batters with pre-emulsified sesame oil had higher water holding capacity than the control. Overall, the batters with pre-emulsified sesame oil enabled lowering of fat and energy contents, making the pork batter had better texture.

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Abstract This study investigated the in vitro performance of the commercial bis-acryl composite resins Systemp C&B II (SYS, Ivoclar Vivadent), Protemp 4 (PT4, 3M ESPE), Structur 2C (ST2, Voco) and ProviPlast (PVP, Biodinamica). Characterization involved optical (color stability, translucency parameter, fluorescence), surface (roughness, morphology and elemental composition), physical-chemical (viscosity, polymerization kinetics) and mechanical analyses (Poisson ratio, biaxial flexural strength, flexural modulus). Most tests were carried out after 24 h, but optical and mechanical analyses were carried out after storage in water at 37 °C for 1, 15, and 30 days. Data were statistically analyzed (a=0.05). Most results were material dependent. SYS and PT4 showed stability in color and translucency over time. All materials had similar or higher fluorescence than human enamel. SC2 and PVP showed rougher surfaces than the other bis-acryl composites. Smaller filler particles were observed on the surface of PT4 and PVP compared with the coarser particles from ST2 and SYS. Viscosity readings indicated a thixotropic behavior for all tested materials. SYS had the lowest and PT4 the highest degree of C=C conversion after 10 min. In the polymerization kinetics, PT4 had the highest maximum polymerization rate and reached earlier the transition between polymerization autoacceleration and autodeceleration. PT4 and SYS had significantly higher flexural strength and modulus than ST2 and PVP for most storage times. Results for Poisson ratio varied between materials. Longer storage periods were generally associated with higher frequency of catastrophic failures in the flexural tests. In conclusion, the performance of bis-acryl composite resins varied largely among materials.

Resumo Este estudo investigou o desempenho in vitro de quatro resinas compostas bisacrílicas comerciais: Systemp C&B II (SYS, Ivoclar Vivadent), Protemp 4 (PT4, 3M ESPE), Structur 2C (ST2, Voco) e ProviPlast (PVP, Biodinamica). A caracterização envolveu análises ópticas (estabilidade de cor, parâmetro de translucidez, fluorescência), de superfície (rugosidade, morfologia e composição elementar), físico-químicas (viscosidade, cinética de polimerização) e mecânicas (razão de Poisson, resistência à flexão biaxial, módulo de elasticidade). A maioria dos testes foram realizados após 24 h, enquanto análises ópticas e mecânicas foram realizadas após armazenamento em água a 37 °C por 1, 15 e 30 dias. Os dados foram analisados estatisticamente (a=0,05). Grande parte dos resultados foi dependente do material. SYS e PT4 mostraram estabilidade de cor e translucidez ao longo do tempo. Todos os materiais apresentaram fluorescência similar ou maior que o esmalte humano. SC2 e PVP apresentaram superfícies mais rugosas que os outros materiais. Menores partículas de carga foram observadas na superfície de PT4 e PVP comparadas às partículas mais irregulares de ST2 e SYS. As leituras de viscosidade indicaram comportamento tixotrópico para todos os materiais testados. SYS teve a menor e PT4 o maior grau de conversão de C=C após 10 min. Na cinética de polimerização, PT4 teve a maior taxa máxima de polimerização e atingiu mais cedo a transição entre autoaceleração e autodesaceleração da polimerização. PT4 e SYS apresentaram resistência à flexão e módulo de elasticidade significativamente maiores que ST2 e PVP na maioria dos períodos de armazenamento. Resultados da razão de Poisson variaram entre os materiais. Períodos mais longos de armazenamento foram em geral associados a maior frequência de falhas catastróficas nos testes de flexão. Em conclusão, o desempenho das resinas compostas bisacrílicas variou amplamente entre os materiais.

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A necessidade de reconstruções ósseas nas áreas médico-odontológicas proporcionou um avanço no estudo dos biomateriais. As características físico-químicas dos biomateriais desenvolvidos influenciam nos fenômenos biológicos que ocorrem no processo regenerativo. Sendo assim, o objetivo deste trabalho foi apresentar os resultados da caracterização físico-química de 12 biomateriais utilizados como enxertos ósseos na Implantodontia. A caracterização físico-química englobou análise granulométrica, microscopia eletrônica de varredura (MEV), difração de raios X (DRX), determinação da área superficial específica e cristalinidade das amostras. O resultado demonstrou que todas as amostras inorgânicas eram constituídas de hidroxiapatita, com diferentes faixas granulométricas, área de superfície variando de 0,18 a 81,4 m2/g e cristalinidade variando de baixa a alta, demonstrando que apesar da semelhança de suas composições, os biomateriais analisados apresentaram diferenças de parâmetros físico-químicos.

The need for bone reconstruction in the medical and dental field provided a breakthrough in the study of biomaterials. The physicochemical characteristics of biomaterials are developed directly targeting the biological phenomena occurring in the regenerative process. Therefore, the objective of this study was to present the results of physical-chemical characterization of twelve biomaterials used in Implantology. Physicochemical characterization was carried out by using electron microscopy (SEM), X-ray diffraction (XRD), surface area (BET) measurement and crystallinity of samples. The result reported that all inorganic samples were constituted of hydroxyapatite, with different grain size bands, area of surface varying from 0.18 to 81.4 g/m2 with a low to high crystallinity, demonstrating that although presenting similar compositions, the analyzed biomaterials presents differences on their physicochemical parameters.

Assuntos

RESUMO

Las plantas Quassia amara y Maytenus ilicifolia son conocidas por sus propiedades terapéuticas sobre el aparato digestivo. En el presente trabajo ambas plantas se investigaron unidas, mediante la mezcla de las tinturas obtenidas, con el objetivo de potenciar su acción como fitofármaco. Este estudio resumió las propiedades físico-químicas de las tinturas obtenidas por percolación, con el empleo de una solución hidroalcóholica al 60 % y un tiempo de extracción de 48 h en 2 variantes: 1) mezclas de las tinturas obtenidas de cada planta, al 20 % en una proporción de 10-90 % (QA-MI), la cual se denominó tintura C. 2) Mezcla del material vegetal de ambas plantas en las mismas proporciones anteriores, en el equipo, para obtener la tintura D. Los parámetros evaluados en ambas tinturas (pH, densidad relativa, índice de refracción, sólidos totales), se compararon estadísticamente. Se comprobó que solo los sólidos totales ofrecen diferencias significativas, con valores superiores en la tintura D, la cual fue seleccionada para el estudio de estabilidad. El extracto D se estudió durante 3 meses a 3 temperaturas diferentes: refrigeración, ambiente y 40 °C. Se comprobó que en refrigeración no ocurren cambios en los parámetros evaluados y en las otras temperaturas aparecen ligeros cambios en pH y contenido alcohólico.

The Quassia amara and Maytenus ilicifolia plants are known by its therapeutical properties on digestive tract. In present paper both plants were researched together by means of mixing of tinctures obtained to potentiate its phytopharmacologic action. Present study summarizes the physical-chemical properties of tinctures obtained by percolation using a 60 %-hydroalcoholic solution and a extraction time of 48 hrs in two variants: 1) mixtures of tinctures obtained from each plant to 20 % at a 10-90 % ratio (QA-MI), which was called C-tincture, the mixture of vegetal material in both plants in the same prior ratios in equipment, to obtain D-tincture. Parameters assessed in both tinctures (pH, relative density, refraction rate, total solids) were statistically compared. It was proved that total solids have significant differences with higher values present in D-tincture, which was selected for stability study. D-extract was studied during three months at different temperatures: refrigeration, room-temperature and at 40 ºC. In refrigeration temperature there are not changes in parameters assessed and in the other temperatures there appear slight changes in pH and alcoholic content.

RESUMO

The Dipteryx lacunifera Ducke is an oleaginous legume with high oil and protein content that can be used in human nutrition. The specie is a native of the Piauí and Maranhão state in the north east of Brazil. The measure physico-chemical properties of the oil are specific density, refractive index, acid, peroxide, iodine and saponification values of 0.91, 1.4651, 0.60 ( percent oleic acid), 2.81, 70.80 and about 179, respectively. Gas chromatographic analysis of the oil showed the presence of 20.6 percent saturated, 65.1 percent monounsaturated and 14.3 percent polyunsaturated fatty acids. The saturated fatty acids C6:0, C8:0, C12:0 and C17:0 were present in trace (<0.01 percent) amounts while the C16:0, C18:0, C20:0, C22:0 and C24:0 were at concentrations of 10.3, 5.4, 3.4, 0.9 and 0.6 percent of the total fatty acids. Unsaturated fatty acids C18:1, C18:2, C18:3 and C22:2 contents were 65.1, 14.1, 0.3 percent and trace (0.01 percent), respectively. Thermal analysis (TG/DTG) revealed that the thermal decomposition of the oil occurs in two steps corresponding to the unsaturated and saturated fatty acids. The oil, when heated to a temperature of 180º C for 400 min showed smaller loss in mass than commercial soy, sunflower and corn oils. The curve DSC indicated an endothermic event with enthalpy variation (DH) of -56.7 Cal.g-1 in the temperature interval of 340 ºC (Ti) the 463º C (Tf), with maximum in 411.1º C (Tm).

A Dipteryx lacunifera Ducke (fava de morcego) é uma leguminosa oleaginosa com elevado conteúdo em proteínas e óleo podendo ser usada na nutrição humana. A espécie é nativa dos estados do Piauí e Maranhão do nordeste do Brasil. Mensurações das propriedades físico-químicas do óleo densidade especifica, índice de refração, acidez, peróxidos, iodo e saponificação foram 0.91, 1.4651, 0.60 ( por cento ácido oléico), 2.81, 70.80 e 179, respectivamente. A análise do óleo por cromatografia gasosa mostrou a presença de 20.6 por cento de ácidos graxos saturados, 65.1 por cento de monoinsaturados e 14.3 por cento poliinsaturados. Os ácidos graxos C6:0, C8:0, C12:0 e C17:0 estão presentes em quantidades de traços (<0.01 por cento) enquanto os C16:0, C18:0, C20:0, C22:0 e C24:0 estão em concentrações de 10.3, 5.4, 3.4, 0.9 e 0.6 por cento, respectivamente, dos ácidos graxos totais. O conteúdo dos ácidos graxos insaturados C18:1, C18:2, C18:3 e C22:2 foram 65.1, 14.1, 0.3 por cento e traço (0.01 por cento), respectivamente. A análise térmica (TG/DTG) revelou que a decomposição térmica do óleo ocorre em dois estágios correspondentes aos ácidos graxos insaturados e saturados. O óleo quando aquecido na temperatura de 180º C por 400 min mostrou menor perda massa que o óleo comercial de soja, girassol e milho. A curva DSC indicou um evento endotérmico com variação de entalpia (DH) de -56.7 Cal.g-¹ no intervalo de temperatura 340º C (Ti) a 463º C (Tf), com máximo em 411.1º C (Tm).

RESUMO

Some reasons for the low use of mathematical modeling to control the agricultural environment in Integrated Apple Production (IAP) are the lack of software fitted to Brazilian conditions, the absence of Portuguese language software and the difficulty to obtain data used in such models. The objective of this review is to provide physical-chemical and toxicological data of pesticides used in IAP until 2005/2006 harvest in a single document, easing the access to these data.

Algumas das razões do pouco uso da modelagem matemática para gestão do ambiente no meio agrícola vinculado à Produção Integrada de Maçãs (PIM), são a falta de softwares adequados às condições brasileiras, a falta destes em língua portuguesa e a dificuldade na coleta e organização de dados necessários ao uso de tais modelos. O objetivo desta publicação é atender esta última demanda, fornecendo dados físicoquímicos e toxicológicos dos agrotóxicos na PIM utilizados até a safra de 2005/2006, num documento único, facilitando seu acesso.

RESUMO

Some reasons for the low use of mathematical modeling to control the agricultural environment in Integrated Apple Production (IAP) are the lack of software fitted to Brazilian conditions, the absence of Portuguese language software and the difficulty to obtain data used in such models. The objective of this review is to provide physical-chemical and toxicological data of pesticides used in IAP until 2005/2006 harvest in a single document, easing the access to these data.

Algumas das razões do pouco uso da modelagem matemática para gestão do ambiente no meio agrícola vinculado à Produção Integrada de Maçãs (PIM), são a falta de softwares adequados às condições brasileiras, a falta destes em língua portuguesa e a dificuldade na coleta e organização de dados necessários ao uso de tais modelos. O objetivo desta publicação é atender esta última demanda, fornecendo dados físicoquímicos e toxicológicos dos agrotóxicos na PIM utilizados até a safra de 2005/2006, num documento único, facilitando seu acesso.