Microhardness, diametral tensile strength and color stability of heated resin composites used for luting ceramic veneers.

PURPOSE: To evaluate color change in ceramic veneers luted to enamel with light-cured, dual-cured resin luting agents, or heated resin composites, as well as to evaluate microhardness and diametral tensile strength of these luting agents. METHODS: For color analysis, 0.5 mm-thick leucite-reinforced glass ceramic veneers (IPS Empress CAD) were cemented onto 40 bovine dental blocks (n= 10) using RelyX Ultimate (RU) or RelyX Veneer (RV) resin-based luting agents, or Gradia Direct (GD) and Palfique Lx5 (P) heated resin composites. After luting, the specimens were subjected to thermocycling (10,000 cycles). Color analysis was performed before and after thermocycling (L*, a*, b*, ΔEab, ΔE00). For the microhardness (Knoop) and diametral tensile strength tests, specimens (Ø 6 x 2 mm) were made (RU, RV, GD, and P). The specimens were subdivided into eight groups (n=10) and light-cured through different ceramic sheets (thicknesses of 0.5 mm or 1.5 mm). Knoop microhardness was performed on the top surface in a microhardness tester, and diametral tensile strength on a universal testing machine. Data were submitted to statistical analysis, using two-way ANOVA, Tukey, and Kruskal-Wallis tests (α= 0.05). RESULTS: For the general color alteration, there was no statistically significant difference between the luting materials (ΔEab, P= 0.57; ΔE00, P= 0.50). There was no interaction between luting agent and thermocycling, for L* (P= 0.87), a* (P= 0.97) and b* (P= 0.95) values. Thermocycling significantly affected only the L* values (P= 0.047), which increased after the cycles. For microhardness, there was a statistically significant difference considering luting agents and ceramic thickness (P< 0.001). GD heated resin composite presented significantly lower microhardness values than all other materials, at both ceramic thicknesses. At a thickness of 1.5 mm, RU cement had higher microhardness values than RV and P materials. Diametral tensile strength was significantly influenced by luting agent (P= 0.01), but not by ceramic thickness (P= 0.55). Diametral tensile strength of GD resin composite was higher than that of the RU, but neither of these two materials differed from RV and P. CLINICAL SIGNIFICANCE: Heated resin composite, used as luting agents, showed similar color stability to light-cured and dual-cure resin cements, however its microhardness was affected by ceramic thickness.

Beyond Universal Volume Scaling: Tailoring Two-Photon Absorption in Nanomaterials by Heterostructure Design.

Colloidal semiconductor nanomaterials present broadband, with large cross-section, two-photon absorption (2PA) spectra, which turn them into an important platform for applications that benefit from a high nonlinear optical response. Despite that, to date, the only means to control the magnitude of the 2PA cross-section is by changing the nanoparticle volume, as it follows a universal volume scale, independent of the material composition. As the emission spectrum is connected utterly to the nanomaterial dimensions, for a given material, the magnitude of the nonlinear optical response is also coupled to the emission spectra. Here, we demonstrate a means to decouple both effects by exploring the 2PA response of different types of heterostructures, tailoring the volume dependence of the 2PA cross-section due to the different dependence of the density of final states on the nanoparticle volume. By heterostructure engineering, one can obtain 1 order of magnitude enhancement of the 2PA cross-section with minimum emission spectra shift.

Sublethal effects of propiconazole on the metabolism of lambari Deuterodon iguape (Eigenmann 1907), a native species from Brazil.

The objective of this study was to analyze the sublethal effects of propiconazole on Deuterodon iguape, a native fish common in Brazil, which has potential for aquaculture and use as a bioindicator. The hypothesis was to test whether D. iguape has a metabolism similar to Danio rerio so that its use in bioassays may be validated. Lethal concentration (LC50) and metabolic rates were studied in fish exposed to propiconazole. Specific oxygen consumption and ammonia excretion for D. iguape and D. rerio increased by 0.01 µg L-1 and then decreased as the propiconazole concentration increased. The decrease in the averages of specific oxygen consumption at the concentration of 0.1 µg L-1 represented a reduction in the metabolic rate compared to the control of 71% for D. iguape and 40% D. rerio. For the ammonia excretion, at the same concentration, there was a reduction of 68.7% and 45.4% for D. iguape and D. rerio, respectively. When comparing ammonia excretion of the two species for each concentration of propiconazole, there was a significant difference (p < 0.05) in relation to the control and for the highest concentration (0.1 µg L-1). As for specific oxygen consumption, there was a statistically significant difference only for the concentration of 0.1 µg L-1. D. iguape proved to be a good and useful bioindicator for ichthyologists or ecologists in studies of moderate pesticide contamination in freshwater aquatic environments, as its metabolic response was similar to D. rerio.

Replacement of Tifton hay by spineless cactus in Girolando post-weaned heifers´ diets.

This study aims to evaluate the effect of the Tifton 85 hay (Cynodon dactylon L. Pers) replacement by Orelha de Elefante Mexicana spineless cactus (Opuntia stricta [Haw.] Haw) on the nutrient intake and digestibility, growth performance, microbial protein synthesis, and efficiency of dietary nitrogen compound utilization in the diets of Girolando heifers. Twenty-four (3.5 months and 100 kg ± 3.5 kg) Girolando heifers (5/8 Holstein x Gyr) were used and arranged in a completely randomized design. Dry matter, organic matter, crude protein, and neutral detergent fiber decreased linearly as a function of the levels of Tifton hay (TH) replacement by Orelha de Elefante Mexicana spineless cactus (OEM). The non-fiber carbohydrate intake and coefficient of dry matter digestibility increased, while the neutral detergent fiber (NDF) digestibility decreased linearly with the OEM inclusion. After evaluating the growth performance by observing weight gain and morphometric measurements, there were no significant alterations. The urinary volume, nitrogen balance as well as the efficiency of nitrogen retention had increased, while the urinary and plasma urea concentrations had decreased linearly with the OEM inclusion. The results obtained in this study show that Orelha de Elefante Mexicana spineless cactus should replace Tifton hay in post-weaned heifer diets.

Sugarcane bagasse as exclusive roughage for dairy cows in smallholder livestock system.

OBJECTIVE: The study aimed to evaluate sugarcane bagasse as roughage in lactating cow on feed intake, digestibility, ingestive behavior, milk production and composition, and microbial protein synthesis. METHODS: Ten Girolando cows at initial body weight of 450±25.6 kg and at 143.7±30.7 days in milk were assigned in two 5×5 Latin square designs. Five 21-day experimental periods were adopted (1° to 14-day: diets adaptation period; 15° to 21-day: data collection and sampling period). The diets consisted of four different levels of sugarcane bagasse (45%, 50%, 55%, and 60%) and a control diet, commonly adopted in the region, based on spineless cactus (25% sugarcane bagasse), formulated to meet 12 kg/d milk yield. RESULTS: The dry matter (DM), organic matter (OM), and total digestible nutrients intakes and DM and OM digestibilities observed for 45% and 50% bagasse inclusion were similar to control diet, while that 55% and 60% bagasse inclusion were lower. Cows fed control diet, and bagasse diets of 45%, and 50% levels had the nutritional requirements attended, that guaranteed 12 kg/d of milk yield. The crude protein intake and digestibility of cows fed 45%, 50%, and 55% of bagasse inclusion were similar to control diet. The neutral detergent fiber (NDF) intake and digestibility differ for all bagasse diets related to control diet, while the non-fiber carbohydrates intake and digestibility for cows fed 45% of bagasse were similar for control diet. The intakes and digestibilities of nutrients decreased linearly in function of bagasse inclusion; NDF and indigestible NDF intakes did not vary. The ruminating time, feeding and rumination efficiency, microbial protein synthesis and milk yield decreased linearly with sugarcane bagasse inclusion. CONCLUSION: Sugarcane bagasse decreases milk production; however, its inclusion level in between 45% to 50% associated to concentrate could replace diets based on spineless cactus for crossbred dairy cow's producing 12 kg/d of milk.

Carcass characteristics of lambs fed spineless cactus as a replacement for sugarcane.

OBJECTIVE: Fresh sugarcane has been a new roughage source for ruminant's in semiarid regions, a function of the decline of sugar and alcohol industry in recent years. However, there is little data published regarding lambs fed sugarcane associated with spineless cactus. This study evaluated the effect of sugarcane replacement with spineless cactus (0%, 33%, 66%, and 100%) in the diet of Santa Inês lambs on carcass characteristics. METHODS: Thirty-six non-castrated Santa Ines lambs at four months of age and an initial body weight of 22±2.3 kg were assigned in a randomized block design and slaughtered after 70 days of confinement. The effects of spineless cactus as a replacement for sugarcane in the diet of the lambs on the carcass characteristics, commercial cut weight and yield, leg tissue composition, and carcass measurements were studied. RESULTS: The study revealed quadratic behavior in slaughter body weight, and hot and cold carcass weight, with maximum values of 38.60, 18.60, and 18.11 kg and replacement levels of 40.18%, 44.42%, and 43.14%, respectively. The cold carcass yield presented an increasing linear behavior. The compactness index of carcass and leg presented a quadratic effect, with estimated maximal values of 0.28 and 0.57 kg/cm and replacement levels of 43.37% and 45.5%, respectively. The weights of commercial cuts of leg, loin, shoulder, and breast showed quadratic behavior, with maximum values of 2.79, 0.852, 1.46, and 1.30 kg and replacement levels of 49.5, 45.32, 39.0, and 40.7, respectively. For tissue composition, quadratic behavior was verified for leg weight, subcutaneous fat, and total fat. CONCLUSION: The replacement of sugarcane by spineless cactus at level 44% is recommended for finishing lambs considering that this level improved most of the carcass characteristics, weights, and yields of commercial cuts and leg tissue composition.

Two-photon absorption in a series of 2,6-disubstituted BODIPY dyes.

We report on the two-photon absorption spectra of a series of 2,6-disubstituted BODIPY dyes. Depending on the substituents, we observe increasing two-photon absorption cross sections with values up to 350 GM compared to 70 GM in the unsubstituted dye. Quantum chemical calculations are performed to assign the absorption bands and to understand the factors controlling the size of the two-photon absorption cross section. Both the maximum of the two-photon absorption band as well as the red-shift of the whole spectrum correlate with the ability of the substituents to extend the π-electron system of the dye. The above-mentioned intense two-photon absorption band corresponds to the absorption of photons with 1.3 eV, which is at the first near-infrared transparency window for biological tissues. The dyes could thus be suitable for bio-imaging applications.

Spineless cactus as a replacement for sugarcane in the diets of finishing lambs.

The effects of replacement of sugarcane by spineless cactus (0, 33, 66, and 100 % on dry matter (DM) basis) were evaluated on intake, digestibility of nutrients, ingestive behavior, and performance of finishing lambs. Thirty-six non-castrated Santa Ines lambs at 4 months of age and an initial body weight of 22 ± 2.3 kg were assigned in a randomized block design. A quadratic effect was found for intake of DM, organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and digestible organic matter (DOM), with maximum values of 1.31, 1.19, 0.219, 0.358, and 0.845 g/day estimated with 42.5, 38.5, 38.8, 21.3, and 44.9 % replacement level, respectively. The digestibility of DM, OM, CP, and EE increased linearly; however, there was a quadratic effect on NDF digestibility with maximum value estimated of 500 g/kg with 64.2 % replacement level. Rumination time, total chewing, and rumination efficiency decreased linearly with the replacement levels; however, idle time increased linearly. A quadratic effect was found for final weight, body weight gain, and total weight gain with maximum values estimated of 38.6 kg, 0.232 kg/day, and 16.2 kg with 39.1, 38.2, and 40.4 % replacing levels. The replacement of 49.5 % sugarcane by spineless cactus can be recommended as optimal level, and problems related to intake, digestibility, and performance are concentrated outside that level.

The potential of salivary albumin to degrade composite resin.

Albumin is a salivary enzyme capable of cleaving ester linkages and catalyzing degradation of resin-based dental materials. However, the effect of concentration-dependent esterolytic action on composite resins as yet remains unexplored. Aim: The purpose of this study was to evaluate whether artificial saliva formulations with different concentrations of albumin affected the surface roughness, flexural strength and microhardness of a composite resin. Materials and Method: Specimens (25x2x2mm) of a nanofilled composite (Filtek Z350XT, 3M/ESPE) were prepared and analyzed for average surface roughness (Ra/pm). The specimens were then allocated to 6 groups (n=30), to be treated with different salivary albumin concentrations: 0, 10, 50, 100, 200, 400 pg/mL. The specimens were stored in their respective artificial saliva groups, half of them for 24 h and the remainder for 180 days (artificial saliva renewed weekly), after which they were submitted to a new Ra reading, and tested for three-point flexural strength (FS, MPa). The specimens stored for 180 days were analyzed for Knoop microhardness (KH, Kg/mm2). Data were submitted to two-way ANOVA (Ra and FS) and one-way ANOVA (KH). Results: Although Ra increased (p < 0.001) and FS decreased (p < 0.001) from 24 hours to 180 days of storage, the albumin concentration did not significantly affectRa (p = 0.168), FS (p = 0.477) or KH (p = 0.378). Conclusion: The esterolytic action of albumin did not increase the artificial-saliva-induced hydrolytic degradation of the composite resin.

Albumina, uma enzima encontrada na saliva, é capaz de clivar ligagoes éster e catalisar a degradando de materiais dentários á base resina. Apesar da agao esterolítica ser potencialmente concentragao-dependente, a investigando desse efeito sobre resinas compostas ainda permanence inexplorado. Objetivo: O objetivo deste estudo foi avaliar se formulagoes de saliva artificial contendo diferentes concentragoes de albumina afetariam a rugosidade superficial, a resistencia flexural e a microdureza de uma resina composta. Materials e Método: Corpos de pro-va em barra (25x2x2mm) foram confeccionados a partir de uma resina composta nanoparticulada (Filtek Z350XT, 3M/ESPE) e foram submetidos á leitura de rugosidade superficial média inicial (Ra, pm), em rugosímetro. Entao, as amostras foram divididas em 6 grupos (n=30) de acordo com a concentrando de albumina na saliva: 0, 10, 50, 100, 200, 400 pg/mL. As amostras foram armazenadas nas formulagoes de saliva artificial correspondente ao seu grupo, metade por 24 h e as demais por 180 dias (com trocas de saliva semanais). As amostras foram submetidas a no-vas leituras de rugosidade (Rafinal) e avaliadas quanto á resistencia flexural de tres pontos (RF, MPa). As amostras armazenadas por 180 dias foram avaliadas quanto á microdureza Knoop (KH, Kg/mm2). Os dados foram submetidos a análises de variáncia a dois critérios (Ra e RF) e a um critério (KH). Resultados: Apesar de haver aumento na Ra (p < 0,001) e uma diminuigao da RF (p < 0,001) de 24 h para 180 dias, a concentragao de albumina nao afetou significativamente a Ra (p = 0,168), a RF (p = 0,477) ou a KH (p = 0,378). Conclusoes: A agdo esterolítica da albumina nao aumentou a degradagao hidrolítica da resina composta induzida pela saliva artificial.

Physical-Exercise-Induced Antioxidant Effects on the Brain and Skeletal Muscle.

Erythroid-related nuclear factor 2 (NRF2) and the antioxidant-responsive-elements (ARE) signaling pathway are the master regulators of cell antioxidant defenses, playing a key role in maintaining cellular homeostasis, a scenario in which proper mitochondrial function is essential. Increasing evidence indicates that the regular practice of physical exercise increases cellular antioxidant defenses by activating NRF2 signaling. This manuscript reviewed classic and ongoing research on the beneficial effects of exercise on the antioxidant system in both the brain and skeletal muscle.

Neuroinflammation in autism spectrum disorders: Exercise as a "pharmacological" tool.

The worldwide prevalence of ASD is around 1%. Although the pathogenesis of ASD is not entirely understood, it is recognized that a combination of genetic, epigenetics, environmental factors and immune system dysfunction can play an essential role in its development. It has been suggested that autism results from the central nervous system derangements due to low-grade chronic inflammatory reactions associated with the immune system activation. ASD individuals have increased microglial activation, density, and increased proinflammatory cytokines in the several brain regions. Autism has no available pharmacological treatments, however there are pedagogical and psychotherapeutic therapies, and pharmacological treatment, that help to control behavioral symptoms. Recent data indicate that exercise intervention programs may improve cognitive and behavioral symptoms in children with ASD. Exercise can also modify inflammatory profiles that will ameliorate associated metabolic disorders. This review highlights the involvement of neuroinflammation in ASD and the beneficial effects of physical exercise on managing ASD symptoms and associated comorbidities.

A selective molecularly imprinted polymer-solid phase extraction for the determination of fenitrothion in tomatoes.

A new and selective sorbent for molecularly imprinted solid-phase extraction (MISPE) was developed and applied for the determination of residues of fenitrothion (FNT) in tomatoes, using HPLC coupled to photodiode array detection (HPLC-DAD). Using FNT as the template molecule, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, toluene as the porogenic solvent, and bulk polymerization as the synthetic method, a molecularly imprinted polymer (MIP) was synthesized. In order to choose the medium which promotes the best molecular recognition of FNT by the MIP, the adsorption of FNT by the MIP was studied in different media containing acetonitrile and toluene. Besides FNT, three structurally related compounds were used to evaluate the selectivity of the FNT-molecularly imprinted polymer. The MIP exhibited the highest selective rebinding to FNT. The method developed was validated, using fortified blank tomato samples. The extraction efficiency was 96%. The limits of detection and quantitation were 0.050 and 0.130 microg g(-1), respectively. The intra-day precision was 5.9% and the inter-day precision 8.1%. The accuracy was higher than 89% for a concentration level around the maximum residue limit of 0.5 microg g(-1).

Epigenetic modifications induced by exercise: Drug-free intervention to improve cognitive deficits associated with obesity.

Obesity and metabolic disorders are increasing worldwide and are associated with brain atrophy and dysfunction, which are risk factors for late-onset dementia and Alzheimer's disease. Epidemiological studies demonstrated that changes in lifestyle, including the frequent practice of physical exercise are able to prevent and treat not only obesity/metabolic disorders, but also to improve cognitive function and dementia. Several biochemical pathways and epigenetic mechanisms have been proposed to understand the beneficial effects of physical exercise on cognition. This manuscript revised central ongoing research on epigenetic mechanisms induced by exercise and the beneficial effects on obesity-associated cognitive decline, highlighting potential mechanistic mediators.

Jovens universitários e a vulnerabilidade masculina às infecções sexualmente transmissíveis / Young college students and male vulnerability to sexually transmitted infections / Jóvenes estudiantes universitarios y vulnerabilidad masculina a las infecciones de transmisión sexual

Objetivo: analisar os comportamentos sexuais e as práticas de prevenção de infecções sexualmente transmissíveis de estudantes universitários do sexo masculino. Métodos: estudo descritivo, quantitativo, transversal, realizado em uma universidade privada, no Rio de Janeiro, Brasil. Foi selecionada uma amostra intencional de 126 estudantes, da área de ciências humanas, na faixa etária de 18 a 29 anos. Foram atendidos todos os aspectos éticos e legais em pesquisa. Resultados: Estudantes na faixa etária entre 18-21 anos representaram 76,19% dos participantes; a maioria teve a primeira relação sexual entre 12-16 anos (71,68%) e possuíam parceiros sexuais - fixos (75,24%) e casuais (73,33%). Usaram preservativos: na sexarca 66,37% e com parceiros casuais 63,64%; não o utilizavam em todas as relações sexuais 61,06% dos participantes. Conclusão: as vulnerabilidades apontam a necessidade de estímulos à adoção de práticas profissionais voltadas à educação em saúde do homem sobre as Doenças Sexualmente Transmissíveis. (AU)

Objective: analyze the sexual behaviors and sexually transmitted infections prevention practices of male university students. Methods: descriptive, quantitative, cross-sectional study carried out at a private university in Rio de Janeiro, Brazil. An intentional sample of 126 students in the humanities, aged 18 to 29 years, was selected. All ethical and legal aspects of research were met. Results: Students aged between 18-21 years represented 76.19% of participants; most had their first sexual intercourse between 12-16 years old (71.68%) and had sexual partners - steady (75.24%) and casual (73.33%). Condoms were used: 66.37% at sexarche and 63.64% with casual partners; 61.06% of the participants did not use it in all sexual relations. Conclusion: the vulnerabilities point to the need to encourage the adoption of professional practices aimed at men's health education on Sexually Transmitted Diseases. (AU)

Objetivo: analizar los comportamientos sexuales y las prácticas de prevención de infecciones de transmisión sexual de estudiantes universitarios varones. Métodos: estudio descriptivo, cuantitativo, transversal, realizado en una universidad privada de Río de Janeiro, Brasil. Se seleccionó una muestra intencional de 126 estudiantes de humanidades, de 18 a 29 años. Se cumplieron todos los aspectos éticos y legales de la investigación. Resultados: Los estudiantes de 18 a 21 años representaron el 76,19% de los participantes; la mayoría tuvo su primera relación sexual entre los 12-16 años (71,68%) y tuvo parejas sexuales, estables (75,24%) y casuales (73,33%). Se utilizaron condones: 66,37% en sexarche y 63,64% con parejas casuales; El 61,06% de los participantes no lo utilizó en todas las relaciones sexuales. Conclusión: las vulnerabilidades apuntan a la necesidad de incentivar la adopción de prácticas profesionales orientadas a la educación para la salud de los hombres en Enfermedades de Transmisión Sexual. (AU)

Construção e Evidências Psicométricas da Escala de Gratidão / Construction and Psychometric Evidence of the Gratitude Scale

Objetivamos construir e analisar as propriedades psicométricas de um instrumento para avaliar a gratidão em formato de julgamento situacional. Após a análise de juízes e estudo piloto, houve a exclusão de 6 itens dos 15 elaborados inicialmente. No estudo de busca de evidência de validade por meio da estrutura interna participaram 514 pessoas, sendo 56% do sexo femini-no, com idades entre 14 e 72 anos, que responderam à Escala de Gratidão, Escala de Afetos, Escala de Vitalidade e a Escala de Satisfação com a Vida. A análise fatorial exploratória indicou uma estrutura unidimensional composta por 9 itens. As mulheres apresentaram as maiores mé-dias quando comparadas aos homens, tanto no julgamento como na autoavaliação da gratidão. A gratidão apresentou correlação, em sentido positivo com magnitude fraca, apenas com a vi-talidade. Os dados indicaram evidências de validade com base no conteúdo do teste, consistên-cia interna e na relação com variáveis externas para a Escala de Gratidão. (AU)

We aimed to build and analyze the psychometric properties of an instrument to assess grati-tude in situational judgment format. After the analysis of judges’ and pilot study, 6 items out of the 15 elaborated were excluded. In the internal structure study 514 people participated, being 56% female, aged between 14 and 72 years old, who answered the Gratitude Scale, Af-fections Scale, Vitality Scale and Life Satisfaction Scale. The exploratory factor analysis indi-cated a one-dimensional structure composed of 9 items. Women had the highest averages when compared to men, both in judgment and in the self-assessment of gratitude. The grati-tude presented positively correlation with weak magnitude only with vitality, being positively explained by the gratitude. The data indicated evidence of validity based on the test content, on its internal consistency and in the relationship to external variables for the Gratitude Scale. (AU)

18REST: a short RIASEC-interest measure for large-scale educational and vocational assessment.

The construction of the 18REST, a short 18-item inventory to describe students' position on John Holland's RIASEC interest types, is documented. The instrument is meant to be used in large-scale assessment in education and on the labor market, supplementing information on school achievement and social-emotional skills. This research was carried out in Brazil, initially with two independent samples composed by adolescents and adults. The 18REST's psychometric properties are compared to those of the more extended RIASEC item pool and confirmed in a new independent undergraduate sample. Despite differences between genders were found as expected, invariance measurement across gender was indicated. Different ways to use the 18REST in large-scale assessment are discussed.

The potential of salivary albumin to degrade composite resin / Albumina salivar: investigando seu potencial de degradar resinas compostas

ABSTRACT Albumin is a salivary enzyme capable of cleaving ester linkages and catalyzing degradation of resin-based dental materials. However, the effect of concentration-dependent esterolytic action on composite resins as yet remains unexplored. Aim: The purpose of this study was to evaluate whether artificial saliva formulations with different concentrations of albumin affected the surface roughness, flexural strength and microhardness of a composite resin. Materials and Method: Specimens (25x2x2mm) of a nanofilled composite (Filtek Z350XT, 3M/ESPE) were prepared and analyzed for average surface roughness (Ra/pm). The specimens were then allocated to 6 groups (n=30), to be treated with different salivary albumin concentrations: 0, 10, 50, 100, 200, 400 pg/mL. The specimens were stored in their respective artificial saliva groups, half of them for 24 h and the remainder for 180 days (artificial saliva renewed weekly), after which they were submitted to a new Ra reading, and tested for three-point flexural strength (FS, MPa). The specimens stored for 180 days were analyzed for Knoop microhardness (KH, Kg/mm2). Data were submitted to two-way ANOVA (Ra and FS) and one-way ANOVA (KH). Results: Although Ra increased (p < 0.001) and FS decreased (p < 0.001) from 24 hours to 180 days of storage, the albumin concentration did not significantly affectRa (p = 0.168), FS (p = 0.477) or KH (p = 0.378). Conclusion: The esterolytic action of albumin did not increase the artificial-saliva-induced hydrolytic degradation of the composite resin.

RESUMO Albumina, uma enzima encontrada na saliva, é capaz de clivar ligagoes éster e catalisar a degradando de materiais dentários á base resina. Apesar da agao esterolítica ser potencialmente concentragao-dependente, a investigando desse efeito sobre resinas compostas ainda permanence inexplorado. Objetivo: O objetivo deste estudo foi avaliar se formulagoes de saliva artificial contendo diferentes concentragoes de albumina afetariam a rugosidade superficial, a resistencia flexural e a microdureza de uma resina composta. Materials e Método: Corpos de pro-va em barra (25x2x2mm) foram confeccionados a partir de uma resina composta nanoparticulada (Filtek Z350XT, 3M/ESPE) e foram submetidos á leitura de rugosidade superficial média inicial (Ra, pm), em rugosímetro. Entao, as amostras foram divididas em 6 grupos (n=30) de acordo com a concentrando de albumina na saliva: 0, 10, 50, 100, 200, 400 pg/mL. As amostras foram armazenadas nas formulagoes de saliva artificial correspondente ao seu grupo, metade por 24 h e as demais por 180 dias (com trocas de saliva semanais). As amostras foram submetidas a no-vas leituras de rugosidade (Rafinal) e avaliadas quanto á resistencia flexural de tres pontos (RF, MPa). As amostras armazenadas por 180 dias foram avaliadas quanto á microdureza Knoop (KH, Kg/mm2). Os dados foram submetidos a análises de variáncia a dois critérios (Ra e RF) e a um critério (KH). Resultados: Apesar de haver aumento na Ra (p < 0,001) e uma diminuigao da RF (p < 0,001) de 24 h para 180 dias, a concentragao de albumina nao afetou significativamente a Ra (p = 0,168), a RF (p = 0,477) ou a KH (p = 0,378). Conclusoes: A agdo esterolítica da albumina nao aumentou a degradagao hidrolítica da resina composta induzida pela saliva artificial.

Conhecimento e práticas de prevenção às infecções sexualmente transmissíveis entre homens jovens universitários* / Knowledge and practices of sexually transmitted infection prevention among young male university students / Conocimientos y prácticas para prevenir Infecciones de Transmisión Sexual entre jóvenes universitarios

Objetivo: identificar o conhecimento e as práticas de prevenção às infecções sexualmente transmissíveis (IST) entre homens jovens universitários. Método: estudo descritivo-exploratório, de natureza qualitativa, realizado em uma universidade pública. Participaram 20 universitários do sexo masculino, na faixa etária de 18 a 29 anos e sexualmente ativos. Realizou-se a coleta de dados por meio de um roteiro semiestruturado e os dados foram analisados pela técnica de análise de conteúdo temático-categorial. Resultados: apesar de os participantes reconhecerem que as IST são transmitidas pela prática do sexo desprotegido, a imprevisibilidade das práticas sexuais, a confiança na parceria sexual em relacionamentos estáveis e o consumo de bebidas alcoólicas são fatores que favorecem o não uso de preservativos. Testes diagnósticos e antirretrovirais são adotados em substituição ao uso de preservativos. Conclusão: o grupo populacional se expõe a riscos e carece de ações de educação em saúde e acesso a serviços de prevenção de doenças.

Objective: to identify the knowledge and prevention practices regarding sexually transmitted infections (STIs) among young male university students. Method: a qualitative nature descriptive-exploratory study, conducted at a public university. 20 sexually active male university students between 18 and 29 years old participated in the study. Data collection was conducted using a semi-structured script, and the data were analyzed using the thematic-categorical content analysis technique. Results: despite participants recognizing that sexually transmitted infections (STIs) are transmitted through unprotected sex, factors such as unpredictability of sexual practices, trust in sexual partners in stable relationships, and alcohol consumption favor the non-use of condoms. Diagnostic tests and antiretroviral medications are adopted as substitutes for condoms use. Conclusion: the population group exposes itself to risks and lacks health education initiatives and access to disease prevention services.

Objetivo: identificar conocimientos y prácticas para prevenir infecciones de transmisión sexual (ITS) entre jóvenes universitarios. Método: estudio descriptivo-exploratorio, de carácter cualitativo, realizado en una universidad pública. Participaron veinte estudiantes universitarios varones, con edades entre 18 y 29 años y sexualmente activos. La recolección de datos se realizó mediante un guion semiestructurado y los datos se analizaron mediante la técnica de análisis de contenido temático-categórico. Resultados: aunque los participantes reconocen que las ITS se transmiten a través de relaciones sexuales sin protección, la imprevisibilidad de las prácticas sexuales, la confianza en las parejas sexuales, en relaciones estables y el consumo de bebidas alcohólicas son factores que favorecen el no uso del condón. Se adoptan pruebas diagnósticas y antirretrovirales en sustitución del uso de preservativos. Conclusión: el grupo poblacional está expuesto a riesgos y requiere acciones de educación en salud y acceso a servicios de prevención de enfermedades.

Mediating effect of career adaptability in levels of hope, satisfaction and depressive symptomatology in postgraduate students / Efeito mediador da adaptabilidade de carreira nos níveis de esperança, satisfação e sintomatologia depressiva em pós-graduandos / Efecto mediador de la adaptabilidad de carrera sobre los niveles de esperanza, satisfacción y síntomas depresivos en estudiantes de posgrado

The objective of this study was to verify the mediating effect of career adaptability in levels of depressive symptomatology, hope, and satisfaction in postgraduate students in Stricto Sensu, and, as well as differences based on sociodemographic variables. A total of 2115 postgraduate students participated, with an average age of 28.91 years (SD = 5.17), 51.8% of whom were Master's degree students, and 74.4% were female. Participants responded to the Career Adapt-abilities Scale, Cognitive Hope Scale, and Baptista Depression Scale (adult version). The results indicated higher levels of depressive symptomatology for scholarship students and in the final phase of the course. The structural equations model indicated that career adaptability has a mediating effect over hope and depressive symptomatology. Self-centered hope and satisfaction on being a post-graduate student directly influence the level of career adaptability and depressive symptoms.

O objetivo foi verificar o efeito mediador da adaptabilidade de carreira em relação à sintomatologia depressiva, esperança e satisfação em estudantes de Pós-Graduação Stricto Sensu, bem como diferenças em função de variáveis sociodemográficas. Participaram 2115 discentes, com idade média de 28,91 anos (DP = 5,17), sendo 51,8% alunos de mestrado e 74,4% do gênero feminino. Os participantes responderam a Escala de Adaptabilidade de Carreira, Escala de Esperança Cognitiva e Escala Baptista de Depressão (versão adulto). Os resultados indicaram maiores níveis de sintomatologia depressiva para alunos bolsistas e em fase final do curso. O modelo de equações estruturais indicou que a adaptabilidade de carreira tem efeito mediador entre a esperança e a sintomatologia depressiva. A esperança autocentrada e a satisfação em ser pós-graduando influenciaram diretamente no nível de adaptabilidade de carreira e nos sintomas depressivos.

El objetivo fue verificar el efecto mediador de la adaptabilidad a la carrera en relación a los síntomas depresivos, la esperanza y la satisfacción en los posgraduados, en Stricto Sensu, así como las diferencias en función de las variables sociodemográficas. Participaron 2115 estudiantes, con una edad promedio de 28,91 años (DE = 5,17), de los cuales el 51,8% eran estudiantes de maestría y el 74,4% mujeres. Los participantes respondieron la Escala de Adaptabilidad de Carrera, la Escala de Esperanza Cognitiva y la Escala de Depresión Bautista (versión para adultos). Los resultados indicaron niveles más altos de síntomas depresivos para los estudiantes becados y en la etapa final del curso. El modelo de ecuación estructural indicó que la adaptabilidad a la carrera tiene un efecto mediador entre la esperanza y los síntomas depressivos. La esperanza autocentrada y la satisfacción de ser un estudiante de posgrado influyen directamente en el nivel de adaptabilidad a la carrera y los síntomas depresivos.

Associações entre autoeficácia e burnout em docentes do ensino superior / Associations between self-efficacy and burnout in higher education teachers

Esta pesquisa pretendeu investigar correlações entre crenças de autoeficácia e síndrome de burnout em professores do ensino superior, verificar a prevalência de burnout, assim como averiguar associações entre a existência de burnout e a percepção da Autoeficácia com características sociodemográficas. Foram utilizadas a Escala de Autoeficácia do Professor nas dimensões Intencionalidade da Ação e Manejo de Classe, e o Maslach Burnout Inventory (MBI) nas dimensões Exaustão Emocional, Despersonalização e Realização Profissional em 356 participantes. Apesar de estes professores apresentarem crenças de autoeficácia fortalecidas, há indicativos da síndrome de burnout em 41,6% dos docentes nos diversos graus de gravidade, porém apenas 0,3% estão em estágio severo, afetando mais mulheres e docentes com menor titulação. Identificou-se associações significativas entre a presença de burnout e a Autoeficácia docente, indicando que quanto menor a autoeficácia percebida, maior a propensão ao burnout.