Class of self-dual models in three dimensions

In the present paper we introduce a hierarchical class of self-dual models in three dimensions, inspired in the original self-dual theory of Towsend-Pilch-Nieuwenhuizen. The basic strategy is to explore the powerful property of the duality transformations in order to generate a new field. The generalized propagator can be written in terms of the primitive one (first order), and also the respective order and disorder correlation functions. Some conclusions about the charge screening and magnetic flux were established. ©1999 The American Physical Society.

Effect of dentinal surface preparation on bond strength of self-etching adhesive systems

The aim of this study was to evaluate the effects of dentin surface treatments on the tensile bond strength (TBS) of the self-etching primer Clearfil SE Bond (CSE) and the one-step self-etching One-Up Bond F (OUB). The exposed flat dentin surfaces of twenty-four sound third molars were prepared with diamond bur at high-speed, carbide bur at low-speed or wet ground with #600 grit SiC paper. The adhesive systems were applied to the dentin surfaces and light-cured according to the manufacturers' instructions. A 6-mm high composite crown was incrementally built-up and each increment was light-cured for 40 seconds. After being stored in water (37°C/24 h), the samples were serially sectioned parallel to the long axis, forming beams (n = 20) with a cross-sectional area of approximately 0.8 mm 2. The specimens were tested in a Universal Testing Machine at 0.5 mm/min. The cross-sectional area was measured and the results (MPa) were analyzed by two-way ANOVA and Tukey Test (p < 0.05). Overall, the groups treated with CSE exhibited the highest TBS for all surface treatments. Dentin surfaces prepared with carbide bur at low speed reduced TBS in the CSE group; however, OUB was not affected by surface treatments. The effect of surface abrasive methods on TBS was material-dependent.

Tensile bond strength of self-etching versus total-etching adhesive systems under different dentinal substrate conditions

The use of acid etchants to produce surface demineralization and collagen network exposure, allowing adhesive monomers interdiffusion and consequently the formation of a hybrid layer, has been considered the most efficient mechanism of dentin bonding. The aim of this study was to compare the tensile bond strength to dentin of three adhesive systems, two self-etching ones (Clearfil SE Bond - CSEB and One Up Bond F - OUBF) and one total-etching one (Single Bond - SB), under three dentinal substrate conditions (wet, dry and re-wet). Ninety human, freshly extracted third molars were sectioned at the occlusal surface to remove enamel and to form a flat dentin wall. The specimens were restored with composite resin (Filtek Z250) and submitted to tensile bond strength testing (TBS) in an MTS 810. The data were submitted to two-way ANOVA and Tukey's test (p = 0.05). Wet dentin presented the highest TBS values for SB and CSEB. Dry dentin and re-wet produced significantly lower TBS values when using SB. OUBF was not affected by the different conditions of the dentin substrate, producing similar TBS values regardless of the surface pretreatments.

Durability of the bond strength of self-adhesive resin cements to human dentin

This study subjected two self-adhesive resin cements and two conventional resin cements to dry and aging conditions, to compare their microtensile bond strengths (MTBS) to dentin. Using four different luting systems (n = 10), 40 composite resin blocks (each 5x5x4 mm) were cemented to flat human crown dentin surfaces. The specimens were stored in water for 24 hours (37°C), at which point each specimen was sectioned along two axes to obtain beams that were divided randomly into two groups: dry samples, which were tested immediately, and samples that were subjected to accelerated aging conditions (12, 000 thermocycles followed by storage for 150 days). The μTBS results were affected significantly by the luting system used (P < 40001). Only the μTBS of Rely-X Unicem was reduced significantly after aging; the μTBS remained stable or increased for the other self-adhesive resin cement and the two conventional cements.

Comparative analysis between experimental characterization results and numerical fdtd modeling of self-assembled photonic crystals

This paper presents a comparative analysis between the experimental characterization and the numerical simulation results for a three-dimensional FCC photonic crystal (PhC) based on a self-assembly synthesis of monodispersive latex spheres. Specifically, experimental optical characterization, by means of reflectance measurements under variable angles over the lattice plane family [1,1, 1], are compared to theoretical calculations based on the Finite Di®erence Time Domain (FDTD) method, in order to investigate the correlation between theoretical predictions and experimental data. The goal is to highlight the influence of crystal defects on the achieved performance.

Coincidences of self-maps on Klein bottle fiber bundles over the circle

The main purpose of this work is to study coincidences of fiber-preserving self-maps over the circle S 1 for spaces which are fiberbundles over S 1 and the fiber is the Klein bottle K. We classify pairs of self-maps over S 1 which can be deformed fiberwise to a coincidence free pair of maps. © 2012 Pushpa Publishing House.

The pros and cons of "self-enumeration"

Includes bibliography

Social cohesion: inclusion and a sense of belonging in Latin America and the Caribbean. Summary

Includes bibliography

Two-year Clinical Performance of Self-etching Adhesive Systems in Composite Restorations of Anterior Teeth

Objective: The aim of this study was to evaluate the two-year clinical performance of Class III, IV, and V composite restorations using a two-step etch-and-rinse adhesive system (2-ERA) and three one-step self-etching adhesive systems (1-SEAs).Material and Methods: Two hundred Class III, IV, and V composite restorations were placed into 50 patients. Each patient received four composite restorations (Amaris, Voco), and these restorations were bonded with one of three 1-SEAs (Futurabond M, Voco; Clearfil S3 Bond, Kuraray; and Optibond All-in-One, Kerr) or one 2-ERA (Adper Single Bond 2/3M ESPE). The four adhesive systems were evaluated at baseline and after 24 months using the following criteria: restoration retention, marginal integrity, marginal discoloration, caries occurrence, postoperative sensitivity and preservation of tooth vitality. After two years, 162 restorations were evaluated in 41 patients. Data were analyzed using the chi(2) test (p<0.05).Results: There were no statistically significant differences between the 2-ERA and the 1-SEAs regarding the evaluated parameters (p>0.05).Conclusion: The 1-SEAs showed good clinical performance at the end of 24 months.

Influence of Nd:YAG Laser on the Bond Strength of Self-etching and Conventional Adhesive Systems to Dental Hard Tissues

Purpose: The aim of this study was to investigate the influence of Nd:YAG laser on the shear bond strength to enamel and dentin of total and self-etch adhesives when the laser was applied over the adhesives, before they were photopolymerized, in an attempt to create a new bonding layer by dentin-adhesive melting.Material and Methods: One-hundred twenty bovine incisors were ground to obtain flat surfaces. Specimens were divided into two substrate groups (n=60): substrate E (enamel) and substrate D (dentin). Each substrate group was subdivided into four groups (n=15), according to the surface treatment accomplished: X (Xeno III self-etching adhesive, control), XL (Xeno III + laser Nd:YAG irradiation at 140 mJ/10 Hz for 60 seconds + photopolymerization, experimental), S (acid etching + Single Bond conventional adhesive, Control), and SL (acid etching + Single Bond + laser Nd:YAG at 140 mJ/10 Hz for 60 seconds + photopolymerization, experimental). The bonding area was delimited with 3-mm-diameter adhesive tape for the bonding procedures. Cylinders of composite were fabricated on the bonding area using a Teflon matrix. The teeth were stored in water at 37 degrees C/48 h and submitted to shear testing at a crosshead speed of 0.5 mm/min in a universal testing machine. Results were analyzed with three-way analysis of variance (ANOVA; substrate, adhesive, and treatment) and Tukey tests (alpha=0.05). ANOVA revealed significant differences for the substrate, adhesive system, and type of treatment: lased or unlased (p<0.05). The mean shear bond strength values (MPa) for the enamel groups were X=20.2 +/- 5.61, XL=23.6 +/- 4.92, S=20.8 +/- 4.55, SL=22.1 +/- 5.14 and for the dentin groups were X=14.1 +/- 7.51, XL=22.2 +/- 6.45, S=11.2 +/- 5.77, SL=15.9 +/- 3.61. For dentin, Xeno III self-etch adhesive showed significantly higher shear bond strength compared with Single Bond total-etch adhesive; Nd:YAG laser irradiation showed significantly higher shear bond strength compared with control (unlased).Conclusion: Nd:YAG laser application prior to photopolymerization of adhesive systems significantly increased the bond strength to dentin.

The influence of self-weight of elastic 2D structures in topology optimization via numerical technique Smooth Evolutionary Structural Optimization (SESO)

This paper deals with topology optimization in plane elastic-linear problems considering the influence of the self weight in efforts in structural elements. For this purpose it is used a numerical technique called SESO (Smooth ESO), which is based on the procedure for progressive decrease of the inefficient stiffness element contribution at lower stresses until he has no more influence. The SESO is applied with the finite element method and is utilized a triangular finite element and high order. This paper extends the technique SESO for application its self weight where the program, in computing the volume and specific weight, automatically generates a concentrated equivalent force to each node of the element. The evaluation is finalized with the definition of a model of strut-and-tie resulting in regions of stress concentration. Examples are presented with optimum topology structures obtaining optimal settings. (C) 2012 CIMNE (Universitat Politecnica de Catalunya). Published by Elsevier Espana, S.L.U. All rights reserved.

Cladistic analysis of self-grooming indicates a single origin of eusociality in corbiculate bees (Hymenoptera: Apidae)

Behavioural traits have been used extensively in recent years as an important character source for making phylogenetic inferences. The phylogenetic positions of the members of the Apini subtribe are increasingly being debated, and new characters must be examined. We analysed the presence and absence of certain behavioural patterns, as well as the sequences of some of these patterns, to generate 79 characters. Eleven species comprised the ingroup, and Xylocopini comprised the outgroup. Parsimony analysis showed that the most parsimonious tree was (Euglossina(Bombina(Apina+Meliponina))). This topology is consistent with most studies that use morphological data and the few that use behavioural data, which suggests that advanced eusociality arose only once in a common ancestor of the clade Apina plus Meliponina; however, this hypothesis is inconsistent with our molecular data. Thus we considered behavioural, molecular, and morphological data and recovered the same topology, in which eusociality has a single origin in corbiculate bees.

Growth evolution of self-textured ZnO films deposited by magnetron sputtering at low temperatures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Synchronization enhancement via an oscillatory bath in a network of self-excited cells

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relation between the level of self-mutilation and the concentration of fecal metabolites of glucocorticoids in captive chimpanzees (Pan troglodytes)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)