Effects of basic fibroblast growth factor on density and morphology of fibroblasts grown on root surfaces with or without conditioning with tetracycline or EDTA.

A study was conducted to evaluate in vitro the effect of root surface conditioning with basic fibroblast growth factor (b-FGF) on morphology and proliferation of fibroblasts. Three experimental groups were used: non-treated, and treated with 50 microg or 125 microg b-FGF/ml. The dentin samples in each group were divided into subgroups according to the chemical treatment received before application of b-FGF: none, or conditioned with tetracycline-HCl or EDTA. After contact with b-FGF for 5 min, the samples were incubated for 24 h with 1 ml of culture medium containing 1 x 10(5) cells/ml plus 1 ml of culture medium alone. The samples were then subjected to routine preparation for SEM, and random fields were photographed. Three calibrated and blind examiners performed the assessment of morphology and density according to two index systems. Classification and regression trees indicated that the root surfaces treated with 125 microg b-FGF and previously conditioned with tetracycline-HCl or EDTA presented a morphology more suggestive of cellular adhesion and viability (P = 0.004). The density of fibroblasts on samples previously conditioned with EDTA, regardless of treatment with b-FGF, was significantly higher than in the other groups (P < 0.001). The present findings suggest that topical application of b-FGF has a positive influence on both the density and morphology of fibroblasts.

Surface conditioning of a composite used for inlay/onlay restorations: Effect on μTBS to resin cement

Purpose: To assess the effect of the composite surface conditioning on the microtensile bond strength of a resin cement to a composite used for inlay/onlay restorations. Materials and Methods: Forty-two blocks (6 × 6 × 4 mm) of a microfilled composite (Vita VMLC) were produced and divided into 3 groups (N = 14) by composite surface conditioning methods: Gr1 - etching with 37% phosphoric acid, washing, drying, silanization; Gr2 - air abrasion with 50-l̀m Al2O3 particles, silanization; Gr3 - chairside tribochemical silica coating (CoJet System), silanization. Single-Bond (one-step adhesive) was applied on the conditioned surfaces and the two resin blocks treated with the same method were cemented using RelyX ARC (dual-curing resin cement). The specimens were stored for 7 days in water at 37°C and then sectioned to produce nontrimmed beam samples, which were submitted to microtensile bond strength testing (μTBS). For statistical analysis (one-way ANOVA and Tukey's test, · = 0.05), the means of the beam samples from each luted specimen were calculated (n = 7). Results: μTBS values (MPa) of Gr2 (62.0 ± 3.9a) and Gr3 (60.5 ± 7.9a) were statistically similar to each other and higher than Gr1 (38.2 ± 8.9b). The analysis of the fractured surfaces revealed that all failures occurred at the adhesive zone. Conclusion: Conditioning methods with 50-l̀m Al2O3 or tribochemical silica coating allowed bonding between resin and composite that was statistically similar and stronger than conditioning with acid etching.

Avaliação energética de um sistema de refrigeração por absorção utilizando gás de aterro e gás natural

The current technological development made by the absorption refrigeration system is an economic and ambient alternative in comparison to the vapor cycle, possessing an advantage that uses thermal energy that is less noble. Chillers of absorption are used widely in the air conditioned industries, because they can be set in motion through hot water vapors that burn natural gas, solar energy, biomasses amongst others instead of electricity. These systems allow it to reduce the tips of electric demand and balance the rocking of energy demand. This work has had a main objective to simulate a absorption refrigeration cycle with lithium-water bromide solution using biogas of sanitary landfill, and mixtures of this with natural gas. These results shown to the energy viability of the system burning biogas and its mixtures with natural gas in the generator, when compared with equipments that uses traditional fuels (natural gas, oil diesel, amongst others), for operation the commercial chillers with 15 kW of the refrigeration capacity and temperature of the water in the entrance of 14°C and the exit of 7°C.

Phytoplankton primary productivity in an urban eutrophic reservoir (São Paulo, Brazil)

The aim of this study was to analyze temporal ..d vertical variation of the biomass and of phytoplankton primary productivity in an urban eutrophic reservoir, in relation to the physical and chemical characteristics of the water. The physical and chemical variables of the water were defined in the limnetic region of the reservoir, at depths of 0.0; 0.5; 1.0; 2.0; 3.0 and 4.0 meters. Three samples were taken to define both the physical and chemical variables, concomitantly with the biomass (chlorophyll-a and phaeophytin) and phytoplankton primary productivity (C-14 method). Based on data obtained on differences in depth of the mixture zone and the euphotic zone, it is hypothesised that, depending on the time of the year, phytoplankton is conditioned by differences in the light and nutrient regimes, which change according to the constant loads of nutrients thrown into the system. The highest concentration of chlorophyll-a in the photic zone of the limnetic region was observed in November 2000 (1,197.3 mg Chl L -1) and the lowest in November 1999 (94.0 mg ChI L -1), whereas the profiles of primary activity of phytoplankton presented the highest rates on the surface of the water column, with values varying from 84.7 (May 2000) to 1,376.7mg C m -3 h -1 (December 2000). Annual primary productivity was calculated at 1,567.0gC m -2y -1, considered euproductive. The primary productivity profiles reported in this study are typical of aquatic eutrophic systems, rich in plankton and with low light penetration. It can be stated that Garças Lake is a system that suffers from anthropogenic impact, through receiving large loads of organic pollution, reflecting on the physical and chemical characteristics of the water and on the high values of biomass and primary phytoplankton activity. © National Institute of Ecology, New Delhi.

Shear bond strength of orthodontic brackets bonded using halogen light and light-emitting diode at different debond times

The aim of this in vitro study was to compare the photoactivation effects of QTH (Quartz-Tungsten-Halogen) and LED (Light-Emitting Diode) on the SBS (Shear Bond Strength) of orthodontic brackets at different debond times. Seventy-two bovine lower incisors were randomly divided into two groups according to the photoactivation system used (QTH or LED). The enamel surfaces were conditioned with Transbond self-etching primer, and APC (Adhesive Pre-Coated) brackets were used in all specimens. Group I was cured with QTH for 20 s and Group II with LED for 10 s. Both groups were subdivided according to the different experimental times after bonding (immediately, 24 h and 7 days). The specimens were tested for SBS and the enamel surfaces were analyzed according to the Adhesive Remnant Index (ARI). The statistical analysis included the Tukey's test to evaluate the main effects of photoactivation and debond time on SBS. The Chi-square test was used to compare the ARI values found for each group, and no statistically significant difference was observed. The debond time of 7 days for QTH photoactivation showed statistically greater values of SBS when compared to the immediate and 24 h periods. There was no statistically significant difference between the QTH and LED groups immediately and after the 24 h period. In conclusion, bonding orthodontic brackets with LED photoactivation for 10 s is suggested because it requires a reduced clinical chair time.

Collectives of humans-with-media in mathematics education: Notebooks, blackboards, calculators, computers and ... notebooks throughout 100 years of ICMI

The main aim of this study was to present evidence of the ways in which different media have conditioned and dramatically reorganized education, in general, and mathematics education, in particular. After an introduction of the theme, we discuss the epistemological perspective that provides the foundation for our analysis: the notion of humans-with-media. Then, we briefly illustrate how the medium is related to the scientific production of mathematical knowledge. We take a detour into the world of art to examine how devices and instruments have historically been associated with the production of mathematical knowledge. Then, we review studies on the history of education to show how traditional media were introduced into schools and have influenced education. In particular, we examine how devices such as blackboards and notebooks, which were novelties a 100 years ago, came to be accepted in schools and the mathematical activities that were promoted with their use. Finally, we discuss how information technology has changed education and how the Internet may have an impact on mathematics education comparable to that of the notebook over a century ago. © FIZ Karlsruhe 2009.

Financing for development and middle income-countries: new challenges

Spanish version avalilable at the Library

Landscape reshaping of the asylum of san francisco de paula, located in jaboticabal, Sao Paulo State, Brazil

It is a commonly known fact that there are elderly who have no family or who do not receive any kind of help from their relatives, as the family does not normally have good financial conditions to help them. These elderly live in private or public shelters and generally, they do not have enough money to cover all the necessary costs, and are forced to survive from donations. Those shelters are based, primarily, on nutrition and health. Leisure and wellbeing are usually treated with little attention, but it could be obtained in a simple and effective way: green areas, which normally exist at the site, are often misused, so they can become rest areas through simple landscape projects. It is important to mention that a garden is not just a beautiful place, but it becomes important for the daily life of older people. The objective of this work was to study the need for contemplative leisure and labor in order to improve the life quality of the elderly that live at the San Francisco de Paula Asylum, in Jaboticabal City, Sao Paulo State, Brazil. In this study, a topographic and a photographic survey was conducted and an analysis of the local ground was done. The preferences of the employees and the visitors of the building were also recorded, as well as the critical points of the area. After this primary analysis, the landscape planning was done, with the help of the AutoCAD 2004 software, prioritizing the use of plants that are not dangerous and that are easy maintained. An orchid nursery was also created in order to provide weekly workshops of orchid cultivation.

Small- and medium-sized enterprises' restructuring in a context of transition: a shared process: inter-player effects on efficient boundary choice in the Argentine manufacturing sector

Includes bibliography

Regional interdependencies and macroeconomic crises: notes on MERCOSUR

Includes bibliography

A emergência da noção de comportamento simbólico em neuropsicopatologia

In this article, we present the notion of symbolic behavior in accordance with neuropsychopathology research from the first decades of the past century, carried out particularly in the context of aphasia research. The guiding axis was the presence of this notion in the first work by Merleau-Ponty, The structure of behavior. Based on research by Gelb and Goldstein, the philosopher takes ownership of the semantics of the symbolic and characterizes human corporality based on its capacity to move beyond the immediate nature of the experienced situations. We also show that the circumscription of symbolic behavior was conditioned by theoretical-methodological changes that permitted the passage from localizationist conceptions to globalist attitudes in view of pathological events of cerebral origin.

Expenditures, investment and financing for sustainable development in Brazil

Includes bibliography

Blood cells attachment after root conditioning and PRP application: An in vitro study

Aim: Root conditioning is aimed at smear layer removal and at dental matrix collagen exposure, which may promote periodontal regeneration. This in vitro study assessed smear layer removal, collagen fiber exposure and the influence of PRP (platelet-rich plasma) application on adhesion of blood cells to the root surface using scanning electron microscopy (SEM). Materials and methods: Scaled root samples (n = 160) were set in five groups and conditioned with: group I - control group (saline solution); group II (EDTA 24%); group III (citric acid 25%); group IV (tetracycline hydrochloride 50 mg/ml); group V (sodium citrate 30%). Eighty samples were assessed using the root surface modification index (RSMI). The other eighty samples were set in two groups. The first group (n = 40) received PRP gel application with a soft brush and the second group (n = 40) received PRP application and then a blood drop. The fibrin clot formation was assessed in the first group and the blood cells adhesion was assessed in the second group using the BEAI (blood elements adhesion index). A previously trained, calibrated, and blind examiner evaluated photomicrographs. Statistical analysis was performed using the Kruskal-Wallis's and Dunn's tests. Results: Group III attained the best results for RSMI and BEAI. Moreover, it was the only group showing fibrin clot formation. Conclusion: Citric acid was the most efficient conditioner for smear layer removal, collagen fiber exposure and blood cell adhesion. Moreover, it was the only group showing fibrin clot formation after PRP application. Clinical significance: This study demonstrated that root conditioning followed by PRP application may favor blood cell adhesion on root surface which may optimize periodontal healing.

Concentrações séricas de aspartato aminotransferase e creatinoquinase e concentrações plasmáticas de lactato em equinos da raça Mangalarga Marchador após exercício físico

The aim of this study was evaluate the influence of physical exercise (marcha gait) on serum values of CK and AST and plasmatic values of lactate in Mangalarga Marchador horses trained in Espirito Santo, Brazil. Serum and plasma samples were obtained from 15 horses in four different moments: rest (T0), 5 minutes (T1), 30 minutes (T2) and 2 hours (T3) after the exercise. Lactate analysis revealed values of 1.02 ± 0.41 mmol/L, 2.73 ± 2.43 mmol/L, 1.89 ± 1.24 mmol/L and 1.31 ± 0.60 mmol/L, respectively at T0, T1, T2 and T3. When evaluating AST, the results recorded in T0, T1, T2 and T3 were, respectively, 189.3 ± 56.0 UI/L, 223.9 ± 53.5 UI/L, 186.8 ± 25.8 UI/L and 193.9 ± 44.7 UI/L. Finally, the CK at moments T0, T1, T2 and T3 were, respectively, 113.4 ± 56.3 UI/l, 144.1 ± 70.9 UI/L, 143.0 ± 81.0 UI/L and 173.1 ± 128.0 UI/L. The results showed that marcha gait leaded to significantly increased in plasma lactate and did not alter serum AST and CK, suggesting that the equines used were conditioned to the physical exercised imposed.

Effect of experimental photopolymerized coatings on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion

Objective: This study investigated the effect of experimental photopolymerized coatings, containing zwitterionic or hydrophilic monomers, on the hydrophobicity of a denture base acrylic resin and on Candida albicans adhesion. Methods: Acrylic specimens were prepared with rough and smooth surfaces and were either left untreated (control) or coated with one of the following experimental coatings: 2-hydroxyethyl methacrylate (HE); 3-hydroxypropyl methacrylate (HP); and 2-trimethylammonium ethyl methacrylate chloride (T); and sulfobetaine methacrylate (S). The concentrations of these constituent monomers were 25%, 30% or 35%. Half of the specimens in each group (control and experimentals) were coated with saliva and the other half remained uncoated. The surface free energy of all specimens was measured, regardless of the experimental condition. C. albicans adhesion was evaluated for all specimens, both saliva conditioned and unconditioned. The adhesion test was performed by incubating specimens in C. albicans suspensions (1 × 10 7 cell/mL) at 37 °C for 90 min. The number of adhered yeasts were evaluated by XTT (2,3-bis[2-methoxy-4-nitro-5-sulfophenyl]-5-[{phenylamino} carbonyl]-2H-tetrazolium-hydroxide) method. Results: For rough surfaces, coatings S (30 or 35%) and HP (30%) resulted in lower absorbance values compared to control. These coatings exhibited more hydrophilic surfaces than the control group. Roughness increased the adhesion only in the control group, and saliva did not influence the adhesion. The photoelectron spectroscopy analysis (XPS) confirmed the chemical changes of the experimental specimens, particularly for HP and S coatings. Conclusions: S and HP coatings reduced significantly the adhesion of C. albicans to the acrylic resin and could be considered as a potential preventive treatment for denture stomatitis. © 2012 Elsevier Ltd.