Avaliação do tempo e da concentração do condicionamento com ácido fluorídrico sobre a resistência de união entre cerâmica e cimento resinoso

The aim of this study was to verify through microtensile test the influence of time and concentration of surface conditioning with hydrofluoric acid and its interference in the adhesion of dual resin cement to porcelain.We used 32 bodies of glass-ceramic lithium disilicate system IPS e.max Press LT with dimensions of 6mm thick, 8 mm in length and 8 mm in length, which will be molded to obtain composite resin blocks corresponding to blocks ceramics. Ceramic and resin blocks were divided into 16 groups (n = 4) and numbered according to the concentration of hydrofluoric acid (2.5%, 5%, 7.5% and 10%) and conditioning time (20 seconds, 40 seconds, 1 minute and 2 minutes). The blocks were cleaned in ultrasonic apparatus with distilled water and dried with compressed air, subjected to acid etching and air-jet washed with water, dried with compressed air and received application of silane agent Monobond-S, followed by adhesive Excite ( Ivoclar Vivaden). Each ceramic block was bonded to the corresponding block of resin through the resin cement Multilink Automix. The specimens were cut to obtain nine micro samples for each set of ceramic-resin with 1 mm X 1 mm X 12 mm in length, which were submitted to microtensile test. The results were analyzed with descriptive statistics and analysis of variance with significance level of 5%, revealing that there were statistically significant (p = 0.000001 <0.05). From the Tukey test can be concluded that etching with hydrofluoric acid and 2.5% for 120 seconds gave the best bond strength, however, no statistical difference between the conditioning with the same acid in the concentration of 5.0% for 20 to 40 seconds

A estrutura produtiva da soja e seus impactos: um quadro comparativo entre Paraguai, Argentina e Uruguai

The presented text aims to evaluate the causes that led to the formation of the current agrarian structure in Paraguay, Argentina and Uruguay as well as the characteristics of the agro-export model that takes place in these countries, which is based on production and export of soybeans. Because of its contemporary importance and represent the bulk of agricultural production in the countries under study, is established the objective of identifying the particularities and commonalities between these soybean production, with regard to its production structure and the benefits and impacts generated by this. Finally, statistical historical data are presented, enabling this comparison, showing the development and crucial moments for the establishment of the current standard

Simulação do tempo de descarga de caminhões graneleiros em uma estação de transbordo de carga em Porto Murtinho, MS

In the current decade, inter modal transport is widely discussed. In Brazil road transport is used in excess whereas there could be more focus and investment towards water transport. Water transport presents many benefits like being low cost and low maintenance. Sea and river ports today aren't capable of supporting Brazil's transport needs. Therefore, with this obstacle, this paper consists of an attempt of modeling and simulation of the process of unloading grain cargo from trucks, through simulation with ProModel software, to verify the necessity of installing more tumblers at the cargo unloading station in Porto Murtinho, MS

Estudo comparativo entre subestações ao tempo e subestações isoladas a gás

In this paper are compared two methods of deploying electrical substations, conventional type, when installed at open areas (Air Insulated Switchgear - AIS), and compact gas-insulated (Gas Insulated Switchgear - GIS) when installed inside buildings. With the expansion of urban centers, areas available for deployment of conventional substations become increasingly difficult to find in these locations. Also due to speculation in urban areas, it becomes feasible to install Gas Insulated Switchgear. This paper presents and evaluates criteria with advantages and disadvantages for application of the two methodologies, aiming to assist in decisionmaking moment of choice in deployment of Electric Power Substations in two scenarios. It is expected that at the end of this work, the criteria evaluated assist in this decision making

Alterações hematológicas em cães e gatos sob estresse

The leukocyte count interpretation on the blood helps on understanding about the possible dysfunction showed by the animal. In general, an abnormal leukogram allows the identification of pathological process. A lot of events lead to an increase in the number of neutrophils, among then, inflammatory process, infection and stress. Dependent on the stress mediator that the animal is submited, the leukocyte alteration will be different. Is important to know how the stress acts on the animal organism, changing the hematological parameters, in order to avoid mistakes on diseases‟ diagnosis. It‟s known that after a stress situation, it‟s expected that stress leukogram appears on the hemogram of the animal. However there are different kinds of stress with different responses. It‟s believed that when the animal is under an acute stress situation, a clinical picture of physiologic leukocytosis occurs which is mediated by the epinephrine. This is characterized by neutrophilia, lymphocytosis, monocytosis and eosinofilia. The physiologic leukocytosis is a transient alteration in the leukogram that occurs within minutes of the stimulus and due to fleeting effect of catecolamines it resolves within 20 to 30 minutes. However, if the animal is under chronicle stress, as solitude, it „s expected to find the stress leukogram on the leukogram, that can be noted especially in dogs. The stress leukogram is characterized by leukocytosis, neutrophilia, lymphopenia, monocytosis and eosinopenia. This kind of stress is induced by the glucocorticoids. It´s important to understand that stress leukogram takes time to occur. The variation on time depends on the animal species, although, in general, the glucocorticoides have a peak effects among 4 to 8 hours, which can last from 24 hours to 2 or 3 days

Realismo e impressionismo em contos de Guy de Maupassant

Dans ce texte on a étudié, afin de comprendre et d'analyser les contes réalistes de Guy de Maupassant, comment Erich Auerbach, dans Mimesis (2009), parcourt les sentiers de la littérature occidentale pour dresser un tableau des traits communs qui existent entre les grandes oeuvres réalistes de l'Occident. L'auteur a réalisé des recherches et des commentaires sur les caractéristiques les plus récurrentes du réalisme littéraire dans les oeuvres d'écrivains tels que Homero, Shakespeare, Voltaire, Flaubert, parmi d'autres. Notre recherche vise, dans sa première étape, à présenter, à expliquer ou à identifier dans les contes de Guy de Maupassant, écrivain de la fin du XIXe siècle, les tendances réalistes discutées par ce théoricien et par d'autres au fil du temps, comme, par exemple, Roland Barthes, dans Crítica e verdade (2007), Bersani, dans Le réalisme et la peur du désir (1975) et Philippe Hamon, dans Un discours contraint (1973, p. 411-445). À partir de ces chercheurs, on essaie d'expliciter et d'affirmer le caractère réaliste d'un des maîtres du récit court - sûrement un représentant du réalisme parmi les grands écrivains de cet art - car dans Mimesis (2009) Zola est considéré par Auerbach comme le dernier des grands réalistes français. En plus, pour la deuxième partie de ce travail, on a l'intention de traiter l'émergence de l'impressionnisme artistique en France, et de présenter les concepts et les thèmes qui ont influencé ce mouvement et se présentent dans la construction des récits de Maupassant. Pour le faire, O impressionismo (1962) de Balzi, O impressionismo (1965) de Serullaz, Impressionniste et symboliste devant la presse (1959) de Jacques Lethève, Impressionismo (2010) de Lobstein e autres, mentionnés dans la bibliographie de cette recherche, ont ouvert la voie aux analyses... (Completo abstract click electronic access below)