Adhesive Quality of Self-adhesive and Conventional Adhesive Resin Cement to Y-TZP Ceramic Before and After Aging Conditions

Purpose: This study evaluated the adhesive quality of simplified self-adhesive and conventional resin cements to Y-TZP in dry and aged conditions. Methods: Y-TZP ceramic blocks (N=192) (5 x 5 x 2 mm) were embedded in acrylic resin and randomly divided into two groups, based on surface conditioning: 96% isopropanol or chairside tribochemical silica coating and silanization. Conditioned ceramics were divided into four groups to receive the resin cements (Panavia F 2.0, Variolink II, RelyX U100 and Maxcem). After 24 hours, half of the specimens (n=12) from each group were submitted to shear bond strength testing (0.5 nun/minute). The remaining specimens were tested after 90 days of water storage at 37 degrees C and thermocycling (12,000x, 5 degrees C-55 degrees C). Failure types were then assessed. The data were analyzed using three-way ANOVA and the Tukey's test (alpha=0.05). Results: Significant effects of ceramic conditioning, cement type and storage conditions were observed (p<0.0001). The groups cleaned using alcohol only showed low bond strength values in dry conditions and the bond strength was reduced dramatically after aging. Groups conditioned using silica coating and silanization showed higher bond strengths both in dry and aged conditions. A high number of specimens failed prematurely prior to testing when they were cleaned using 96% isopropanol. Conclusion: Overall, silica coating and silanization showed higher, stable bond strengths with and without aging. The durability of resin-ceramic adhesion varied, depending on the adhesive cement type.

Macrophage suppression following phagocytosis of apoptotic neutrophils is mediated by the S100A9 calcium-binding protein

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Feeding preference of the South American endemic anomuran Aegla platensis (Decapoda, Anomura, Aeglidae)

In order to determine the feeding preference of Aegla platensis in streams and the importance of microorganisms in its detritivore diet, we carried out two experiments designed to evaluate the food preferences of A. platensis (1) among leaves with different levels of microbial colonization and (2) among insect larvae (Chironomidae, Simuliidae, Hydropsychidae) and microbially conditioned leaves. A. platensis preferred animal over plant food items; when only leaves were offered, this aeglid preferred the leaves with higher levels of microorganism conditioning.

Reinforcing properties of fencamfamine: Involvement of dopamine and opioid receptors

Fencamfamine (FCF) is a psychostimulant classified as an indirect dopamine agonist. The conditioning place preference (CPP) paradigm was used to investigate the reinforcing properties of FCF. After initial preferences had been determined, animals were conditioned with FCF (1.75, 3.5, or 7.0 mg/kg; IP). Only at the dose of 3.5 mg/kg FCF produced a significant place preference. Pretreatment with SCH23390 (0.05 mg/kg, SC) or naloxone (1.0 mg/kg SC) 10 min before FCF (3.5 mg/kg; IP) blocked both FCF-induced hyperactivity and CPP. Pretreatment with metoclopramide (10.0 mg/kg; IP) or pimozide (1.0 mg/kg, IP), respectively, 30 min or 4 h before FCF (3.5 mg/kg; IP), which blocked the FCF-induced locomotor activity, failed to influence place conditioning produced by FCF. In conclusion, the present study suggests that dopamine D 1 and opioid receptors are related to FCF reinforcing effect, while dopamine D 2 subtype receptor was ineffective in modifying FCF-induced CPP.

Use of sorghum seed tissue as a biocatalyst in a stirred reactor for oxalic acid determination

The enzyme oxalate oxidase, E.C. 1.2.3.4 from Sorghum vulgare seeds (variety BR303) was used to develop a new sensor for oxalate determination without any purification. The sorghum seeds were conditioned in a 0.10 mol I-1 KCl solution. Then, these seeds were put in a stirring bar type enzymic reactor and coupled with an electrode for CO2. This device was introduced into a cell containing 10.0 ml of a 0.10 mol I-1 KCl solution saturated with oxygen. This sensor showed a linear response between 1.0 and 4.0 × 10-3 mol I-1 with a slope of 30 mV per decade of oxalate concentration at 25.0°C. The sensor was stable for one month or 200 determinations. The response time was about 60 s. The Michaelis-Menten constant determined for this enzyme was 1.5 × 10-3 mol I-1.

Mapeamento do contorno estrutural do embasamento da bacia sedimentar de Curitiba - PR

The sedimentary Curitiba basin is located in the Central-Southern part of the first Parananense plateau, and comprises Curitiba (PR), and part of the neighbour Municipalities (fig.1). It is supposed to be of Plio-Pleistocene age. It has a shallow sedimentary fulfillment, represented by the Guabirotuba formation (BIGARELLA and SALAMUNI, 1962) which is dristributed over a large area of about 3.000km2. The internal geometry, not entirely known yet, is actually object of detailed research, that shows its geological evolution to Cenozoic tectonic movements. For the purpose of this study the definition of the structural contour of the basement and their depo-centers is fundamental. This paper presents the results of the integration of surface and subsurface data, processed by statistical methods, which allowed a more precise definition of the morphostructural framework of the basement. For the analysis of the geological spacial data, specific softwares were used for statistical processing for trend surfaces analysis. The data used in this study are of following types: a) drilling logs for ground water; b) description of surface points of geological maps (CRPM, 1977); c) description of points of geotechnical drillings and down geological survey. The data of 223 drilling logs for ground water were selected out of 770 wells. The description files of 700 outcrops, as well as planialtimetric field data, were used for the localization of the basement outcrop. Thus, a matrix with five columns was set up: utm E-W (x) and utm N-S (y); surface altitude (z); altimetric cote of the contact between sedimentary rocks and the basement (k); isopachs (l). For the study of the basement limits, the analysis of surface trends of 2(nd) and 3(rd) degree polinomial for the altimetric data (figs. 2 and 3) were used. For the residuals the method of the inverse of the square of the distance (fig.4) was used. The adjustments and the explanations of the surfaces were made with the aid of multiple linear regressions. The analysis of 3rd degree polinomial trend surface (fig.3) confirmed that the basement tends to be more exposed towards NNW-SSE explaining better the data trend through an ellipse, which striking NE-SW and dipping SW axis coincides with the trough of the basin observed in the trending surface of the basement. The performed analysis and the respective images offer a good degree of certainty of the geometric model of the Curitiba Basin and of the morphostructure of its basement. The surface trend allows to sketch with a greater degree of confidence the structural contour of the topgraphic surface (figs. 5 and 6) and of the basement (figs. 7 and 8), as well as the delimitation of intermediate structural heights, which were responsible for isolated and assymmetric depocenters. These details are shown in the map of figures 9 and 10. Thus, the Curitiba Basin is made up by a structural trough stretching NE-SW, with maximum preserved depths of about 80m, which are separated by heights and depocenters striking NW-SE (fig. 11). These structural features seems to have been controlled by tectonic reactivation during the Tertiary (HASUI, 1990) and which younger dissection was conditioned by neotectonic processes (SALAMUNI and EBERT, 1994).

VAr planning using genetic algorithm and linear programming

A combined methodology consisting of successive linear programming (SLP) and a simple genetic algorithm (SGA) solves the reactive planning problem. The problem is divided into operating and planning subproblems; the operating subproblem, which is a nonlinear, ill-conditioned and nonconvex problem, consists of determining the voltage control and the adjustment of reactive sources. The planning subproblem consists of obtaining the optimal reactive source expansion considering operational, economical and physical characteristics of the system. SLP solves the optimal reactive dispatch problem related to real variables, while SGA is used to determine the necessary adjustments of both the binary and discrete variables existing in the modelling problem. Once the set of candidate busbars has been defined, the program implemented gives the location and size of the reactive sources needed, if any, to maintain the operating and security constraints.

Alimentary preconditioning in Acromyrmex subterraneus brunneus workers

Ants suffer a strong environmental influence and are sometimes conditioned for many social activities. To understand better this phenomenon in leaf-cutting ants, 24 colonies of Acromyrmex subterraneus brunneus (Hymenoptera: Formicidae) were conditioned for 2 months with 6 different plants (Citrus spp., Ligustrum spp., Acalypha spp., Eucalyptus spp., Alchornea triplinervia, Melia spp.), to verify alimentary preconditioning in plant selection. After the conditioning period, plants were offered simultaneously, to evaluate the acceptability of each plant species. During foraging, the workers did not exhibit alimentary source fidelity, which was familiarized. This fact suggests the absence of alimentary preconditioning, reinforcing the polyphagic foraging behavior of leaf-cutting ants.

The effect of plant diversity on fungus garden development and foraging behavior of leaf-cutting ants (Hymenoptera: Formicidae)

The leaf-cutting ants forage a wide variety of plant species, used for symbiotic fungus cultivation. To better understand this tripartite complex interaction, 24 colonies of Acromyrmex subterraneus brunneus were conditioned for 4 months to 6 different plants (Citrus spp., Ligustrum spp., Acalypha spp., Eucalyptus spp., Alchornea triplinervia, Melia spp.), to verify the influence of conditioning on foraging behavior of workers. The effect of plants on symbiotic fungus development was studied separately, through macerated plants in Agar and culture medium A as the control. During foraging, workers presented polyphagic foraging behavior, refusing the plants to which they were conditioned. The selection of plants is not correlated with the plant substrate that promotes good development of symbiotic fungus. Such results demonstrate the importance of plant diversity for fungus garden maintenance.

The effect of adhesive and flowable composite on postoperative sensitivity: 2-Week results

Objective: To measure 2-week postoperative sensitivity in Class II composite restorations placed with a self-etching adhesive (Clearfil SE Bond) or a total-etch adhesive (Prime&Bond NT) with or without a flowable composite as cervical increment. Method and materials: Upon approval by the University of Guarulhos Committee on Human Subjects, 100 restorations were inserted in 46 patients who required Class II restorations in their molars and premolars. Enamel and dentin walls were conditioned with a self-etching primer (for Clearfil SE Bond) or etched with 34% phosphoric acid (for Prime&Bond NT). A 1- to 2-mm-thick increment of a flowable composite (Filtek Flow) was used in the proximal box in 50% of the restorations of each adhesive. Preparations were restored with a packable composite (Surefil). The restorations were evaluated preoperatively and 2 weeks postoperatively for sensitivity to cold, air, and masticatory forces using a visual analog scale. Marginal integrity of the accessible margins was also evaluated. Statistical analysis used a mixed linear model with subject as a random effect. Results: Ninety-eight teeth from 44 subjects were observed at 2 weeks. The type of adhesive and use of flowable composite had no significant effects or interaction for any of the four outcomes of interest, ie, change from baseline to 2 weeks in sensitivity and response time for the cold or air stimulus. For the air stimulus, the overall average change from baseline was not significant for either sensitivity or response time. For the cold stimulus, the overall average change from baseline was significant for both sensitivity and response time. No case of sensitivity to masticatory forces was observed. Conclusion: No differences in postoperative sensitivity were observed between a self-etch adhesive and a total-etch adhesive at 2 weeks. The use of flowable composite did not decrease postoperative sensitivity.

Diversity of vascular plants growing on walls of a Brazilian city

City walls are very specialized environments, conditioned by human activities. There is little information about plants that invade human-made habitats, and no study done in Brazil with plants growing up on walls. The aim of the present study was to survey the wall vascular flora of a Brazilian city, comparing the diversity found in its downtown and neighborhoods. Fieldwork was done in Jundiaí, São Paulo State, where data was collected in downtown and in five neighborhoods. In each place, three transects of 1 km were established and every plant individual was registered. Twenty-eight species were identified, all of them on the downtown transect and most also on the neighborhood transects. Five species were the most frequent, although none were dominant. The diversity indicies of the six transects were not significantly different, with an overall diversity of H′ = 2.93. © Springer Science + Business Media, Inc. 2006.

Sorption isotherm, glass transitions and state diagram for freeze-dried plum skin and pulp

Differential scanning calorimetry (DSC) was used to determine phase transitions of freeze-dried plums. Samples at low and intermediate moisture contents, were conditioned by adsorption at various water activities (0.11≤a w≤0.90) at 25°C, whereas in the high moisture content region (a w>0.90) samples were obtained by direct water addition, with the resulting sorption isotherm being well described by the Guggenheim-Anderson-deBoer (GAB) model. Freeze-dried samples of separated plum skin and pulp were also analysed. At a w≤0.75, two glass transitions were visible, with the glass transition temperature (T g) decreasing with increasing a w due to the water plasticising effect. The first T g was attributed to the matrix formed by sugars and water. The second one, less visible and less plasticised by water, was probably due to macromolecules of the fruit pulp. The Gordon-Taylor model represented satisfactorily the matrix glass transition curve for a w≤0.90. In the higher moisture content range T g remained practically constant around T g′ (-57.5°C). Analysis of the glass transition curve and the sorption isotherm indicated that stability at a temperature of 25°C, would be attained by freeze dried plum at a water activity of 0.04, corresponding to a moisture content of 12.9% (dry basis). © 2006 SAGE Publications.

Bond strength of a resin cement to high-alumina and zirconia-reinforced ceramics: The effect of surface conditioning

Purpose: The aim of this study was to evaluate the effect of two surface conditioning methods on the microtensile bond strength of a resin cement to three high-strength core ceramics: high alumina-based (In-Ceram Alumina, Procera AllCeram) and zirconia-reinforced alumina-based (In-Ceram Zirconia) ceramics. Materials and Methods: Ten blocks (5 ×6 × 8 mm) of In-Ceram Alumina (AL), In-Ceram Zirconia (ZR), and Procera (PR) ceramics were fabricated according to each manufacturer's instructions and duplicated in composite. The specimens were assigned to one of the two following treatment conditions: (1) airborne particle abrasion with 110-μm Al2O3 particles + silanization, (2) silica coating with 30 μm SiOx particles (CoJet, 3M ESPE) + silanization. Each ceramic block was duplicated in composite resin (W3D-Master, Wilcos, Petrópolis, RJ, Brazil) using a mold made out of silicon impression material. Composite resin layers were incrementally condensed into the mold to fill up the mold and each layer was light polymerized for 40 s. The composite blocks were bonded to the surface-conditioned ceramic blocks using a resin cement system (Panavia F, Kuraray, Okayama, Japan). One composite resin block was fabricated for each ceramic block. The ceramic-composite was stored at 37°C in distilled water for 7 days prior to bond tests. The blocks were cut under water cooling to produce bar specimens (n = 30) with a bonding area of approximately 0.6 mm2. The bond strength tests were performed in a universal testing machine (crosshead speed: 1 mm/min). Bond strength values were statistically analyzed using two-way ANOVA and Tukey's test (≤ 0.05). Results: Silica coating with silanization increased the bond strength significantly for all three high-strength ceramics (18.5 to 31.2 MPa) compared to that of airborne particle abrasion with 110-μm Al2O3 (12.7-17.3 MPa) (ANOVA, p < 0.05). PR exhibited the lowest bond strengths after both Al2O3 and silica coating (12.7 and 18.5 MPa, respectively). Conclusion: Conditioning the high-strength ceramic surfaces with silica coating and silanization provided higher bond strengths of the resin cement than with airborne particle abrasion with 110-μm Al2O3 and silanization.

Genetic effects on preweaning weight gain of Nelore-Hereford calves according to different models and estimation methods

Additive and nonadditive genetic effects on preweaning weight gain (PWG) of a commercial crossbred population were estimated using different genetic models and estimation methods. The data set consisted of 103,445 records on purebred and crossbred Nelore-Hereford calves raised under pasture conditions on farms located in south, southeast, and middle west Brazilian regions. In addition to breed additive and dominance effects, the models including different epistasis covariables were tested. Models considering joint additive and environment (latitude) by genetic effects interactions were also applied. In a first step, analyses were carried out under animal models. In a second step, preadjusted records were analyzed using ordinary least squares (OLS) and ridge regression (RR). The results reinforced evidence that breed additive and dominance effects are not sufficient to explain the observed variability in preweaning traits of Bos taurus x Bos indicus calves, and that genotype x environment interaction plays an important role in the evaluation of crossbred calves. Data were ill-conditioned to estimate the effects of genotype x environment interactions. Models including these effects presented multicolinearity problems. In this case, RR seemed to be a powerful tool for obtaining more plausible and stable estimates. Estimated prediction error variances and variance inflation factors were drastically reduced, and many effects that were not significant under ordinary least squares became significant under RR. Predictions of PWG based on RR estimates were more acceptable from a biological perspective. In temperate and subtropical regions, calves with intermediate genetic compositions (close to 1/2 Nelore) exhibited greater predicted PWG. In the tropics, predicted PWG increased linearly as genotype got closer to Nelore. ©2006 American Society of Animal Science. All rights reserved.

Nova contribuiçao ao conhecimento da formação Rio Claro (T) na Folha Rio Claro (SP)

The Rio Claro Formation mainly occurs in the county of Rio Claro (SP) lying unconformably on Paleozoic and Mesozoic rocks. Its thickness is 30-40 m. It shows fine to coarse, regular to poor sorted, Triable sandstones and conglomerates with quartzite and quartz clasts in the base. Thin layers of mudstone occur interbeded. Stratigraphic maps had been elaborated in recent analyses allowing to improve the knowledge about the formation. The biggest thicknesses occur on the east part of the studied area. The coarse/fine clastic ratio map demonstrates that fine sediments are concentrated in the east side, and suggests the existence of barriers which conditioned perennial water body (or bodies) where decantation took place (east, south and southeast sides). The structural contour map of the Rio Claro Formation base indicates a NW/SE trough which was the main depositional axis. The integrated analysis demonstrates that the formation is formed by lacustrine, fluvial and debris flows deposits whose source area was located on NW side, with coalescent alluvial fans from where braided to psamitic meandering fluvial channels came. The location of the source area suggests no link with the Corumbataf River paleo-terraces.