1000 resultados para imersão
Resumo:
This work consists in a study of the Shrimp Industry in the state of Rio Grande do Norte, whose central issue relates to the understanding of how the Triple Helix (University, Government and the productive sector) interrelationship limits or expands the industry s innovation process. The study aims to understand how the Triple Helix relationship interferes in the innovation process of shrimp in Rio Grande do Norte. As the knowledge becomes the resource key for production methods, the generation of new technologies, new products and processes which demands joint and integrated action of the institutions comprising the Triple Helix: University, Government and productive sector, which possess the essential resources to innovate the process and can be maximized from cooperative relationships between the referred Institutions. Thus, in this work, it was sharply used the pioneering studies of Sabato and Botana (1968) regarding the cooperation relationship between the scientific-technological sphere, the governmental and the productive base, and studies on the Triple Helix approach, proposed by Etzkowitz and Leydesdorff (2000), in which the university has a key role in the process of technological and innovative development of countries and regions, and under which it is assigned to the very University - the character of the entrepreneurial institution, through the concept of entrepreneurial University. Aiming to overcome the criticism of Cooke (2005), regarding the limitations of the Triple Helix approach, in this study it was used - as analytical perspectives - the perspective of social immersion (Granovetter, 1985, 2005) and the theory of resources dependence (PFEFFER; SALANCIK, 1978). The analytical perspectives presented in here, despite of the different assumptions, are essential to eliminate the bias that one only approach can lead (ASTLEY; VAN DE VEM; 2007). The authors arguments focus on the fact that the integration is possible if the researcher acknowledged that different perspectives may have different descriptions of the same phenomenon. As a research strategy, this study is characterized as a study case, along with the proposed objectives - the qualitative method was used as an approach and, depending on the gathering of the sector s historical, a sectional longitudinal view approach was applied (VIEIRA, 2004). The primary and secondary data were used in order to understand the sector s evolutionary process and its inter-institutional relations - regarding the shrimp culture in Rio Grande do Norte - to promote the development, as the content was used for the technical analysis (BARDIN, 1977). The approach of social immersion and resources addiction dependence made it possible to understand that relationships are established within and between each sphere (university, government and productive sector) characterizing a network of low density relationships and strongly internal and external dependence. Based on the speech of Etzkowitz and Mello (2006), a successful Triple Helix strategy of innovation requires not only the involvement and commitment of the parts, within the institutional sphere and among them, but also the development of mechanisms to coordinate the multiple and complex interactions and interfaces, focusing on promoting both environment and context for innovation and learning; it can be acknowledge from study results that the shrimp in the State of the RN, although there are several institutional mechanisms to promote greater integration and technological development, has been presented disjointed - both internally and between the spheres - and under no legitimate practice when facing the innovational promotion and integration institutions. Due to those factors, the central institutions of the network are crucial to the promotion of innovations, spreading through their direct contacts the importance factor of the sustainable competitive activity in the world market and on the national level. However, it may be concluded, from the data, that the Triple Helix relations are interfering in a negative way on what concerns the promotion of innovations in the shrimp industry in RN
Resumo:
This dissertation examines the organizational innovation as a nonlinear process, which occurs in a social and political context and, therefore, socially immersed. Examines the case of shrimp in the state of RN, starting from the following problem: although the norteriograndense shrimp occupies the largest producer of farmed shrimp from Brazil, has a series of bottlenecks concerning the generation of industry innovation, concerning the social relationships and policies between the various actors in the network, whether private or public, and its consequences in terms of opportunity and limits generated for the innovative dynamics. The objective of the research is to understand how the social embeddedness of political actors affects norteriograndense shrimp within the context of structural relations, the industry generation of innovation, throughout its technological trajectory . The approach of social embeddedness balances atomised perspectives, undersocialized and oversocialized, of economic action, considering both the human capacity to act as sources of constraint, whose mechanisms are analyzed the structural and political. In methodological terms this is a case study, analyzed from the research literature, documentary and experimental. Primary data were collected through semi-structured interviews and analyzed in depth by the technique of content analysis. Was adopted a longitudinal approach, seeking to understand the phenomenon from the perspective of the subjects, describing it in an inductive process of investigation. After characterizing the sector and defining their technological trajectory, the analysis of the results followed its four stages: (1) Introduction of Technology: 1973-1980, (2) Intensification of Research: 1981-1991, (3) Technological Adaptation, 1992 -2003, (4) Technological Crisis: 2004-2009. A cross-sectional analysis along the evolutionary trajectory revealed the character of structural changes and policies over time, and implications on the generating process of innovation. Note that, the technological limit to which the sector reached requires changes in technology standards, but is more likely that the potiguar shrimp is entering a new phase of his career in technology rather than a new technological paradigm
Resumo:
The current study analyzes the birth and development of two strategic alliances established between shrimp producers in Rio Grande do Norte: the Unipesca and the Coopercam. To achieve this aim, two approaches which, at first sight, could be considered contradictory were used: the Transactional Costs Economy and Embeddedness. The first approach is fundamentally based in the studies of Williamson (1985; 1991; 1996; 1999; 2000; 2002). Embededness, on the other hand, went through the review of a series of authors, such as Burt (1992), Granovetter (1973; 1985), Uzzi (1997), Gulati (1994; 1995; 1997; 1998; 1999; 2000), Nielsen (2005), Ring (2002), Ring and Van de Ven (1994), Zafirovski (2002), among others. To analyze the birth and development of the cooperatives in this study, Gulati s work (1998) was used. This study shows the steps to be studied for a better comprehension of an alliance: the decision of starting an alliance and the choice of the partners, the decision about the governance structure, the evolution of the alliance and the development of the companies which established this partnership. To carry this study out, a study case accordingly to Yin s proposal (2001) was adopted. Semi-structured interviews with pre-defined plots were conducted in two phases: in the beginning of 2006 and in the beginning of 2007. The subjects from the research were, in 2006, representative members of the main associations and corporations, besides the shrimp producers from the state, when the context of the activity was set. In the second phase, in 2007, representative members from the two cooperatives that were listed above were interviewed the president from Coopercam and the marketing manager from Unipesca. Besides these two members, directors from two important organizations in each of these cooperatives were also interviewed, giving out the necessary information for the research. Secondary data was also collected from the Brazilian Association of Crab producers website, as well as from news from important newspapers in RN, such as Tribuna do Norte. The primary data was analyzed in terms of quality, accordingly to the documental analysis technique. Thus, through the data that was collected, it can be concluded that the reasons that motivated the companies to cooperate can be explained in terms of the transactional costs economy. However, the choice of partners is more connected to aspects approached by the social embededness. When aspects related to development and evolution were analyzed, it could be seen that both aspects from TCE and Embededness were vital to explain the development of the cooperatives mentioned
Resumo:
This work consists in a study of the Shrimp Industry in the state of Rio Grande do Norte, whose central issue relates to the understanding of how the Triple Helix (University, Government and the productive sector) interrelationship limits or expands the industry s innovation process. The study aims to understand how the Triple Helix relationship interferes in the innovation process of shrimp in Rio Grande do Norte. As the knowledge becomes the resource key for production methods, the generation of new technologies, new products and processes which demands joint and integrated action of the institutions comprising the Triple Helix: University, Government and productive sector, which possess the essential resources to innovate the process and can be maximized from cooperative relationships between the referred Institutions. Thus, in this work, it was sharply used the pioneering studies of Sabato and Botana (1968) regarding the cooperation relationship between the scientific-technological sphere, the governmental and the productive base, and studies on the Triple Helix approach, proposed by Etzkowitz and Leydesdorff (2000), in which the university has a key role in the process of technological and innovative development of countries and regions, and under which it is assigned to the very University - the character of the entrepreneurial institution, through the concept of entrepreneurial University. Aiming to overcome the criticism of Cooke (2005), regarding the limitations of the Triple Helix approach, in this study it was used - as analytical perspectives - the perspective of social immersion (Granovetter, 1985, 2005) and the theory of resources dependence (PFEFFER; SALANCIK, 1978). The analytical perspectives presented in here, despite of the different assumptions, are essential to eliminate the bias that one only approach can lead (ASTLEY; VAN DE VEM; 2007). The authors arguments focus on the fact that the integration is possible if the researcher acknowledged that different perspectives may have different descriptions of the same phenomenon. As a research strategy, this study is characterized as a study case, along with the proposed objectives - the qualitative method was used as an approach and, depending on the gathering of the sector s historical, a sectional longitudinal view approach was applied (VIEIRA, 2004). The primary and secondary data were used in order to understand the sector s evolutionary process and its inter-institutional relations - regarding the shrimp culture in Rio Grande do Norte - to promote the development, as the content was used for the technical analysis (BARDIN, 1977). The approach of social immersion and resources addiction dependence made it possible to understand that relationships are established within and between each sphere (university, government and productive sector) characterizing a network of low density relationships and strongly internal and external dependence. Based on the speech of Etzkowitz and Mello (2006), a successful Triple Helix strategy of innovation requires not only the involvement and commitment of the parts, within the institutional sphere and among them, but also the development of mechanisms to coordinate the multiple and complex interactions and interfaces, focusing on promoting both environment and context for innovation and learning; it can be acknowledge from study results that the shrimp in the State of the RN, although there are several institutional mechanisms to promote greater integration and technological development, has been presented disjointed - both internally and between the spheres - and under no legitimate practice when facing the innovational promotion and integration institutions. Due to those factors, the central institutions of the network are crucial to the promotion of innovations, spreading through their direct contacts the importance factor of the sustainable competitive activity in the world market and on the national level. However, it may be concluded, from the data, that the Triple Helix relations are interfering in a negative way on what concerns the promotion of innovations in the shrimp industry in RN
Resumo:
This dissertation examines the organizational innovation as a nonlinear process, which occurs in a social and political context and, therefore, socially immersed. Examines the case of shrimp in the state of RN, starting from the following problem: although the norteriograndense shrimp occupies the largest producer of farmed shrimp from Brazil, has a series of bottlenecks concerning the generation of industry innovation, concerning the social relationships and policies between the various actors in the network, whether private or public, and its consequences in terms of opportunity and limits generated for the innovative dynamics. The objective of the research is to understand how the social embeddedness of political actors affects norteriograndense shrimp within the context of structural relations, the industry generation of innovation, throughout its technological trajectory . The approach of social embeddedness balances atomised perspectives, undersocialized and oversocialized, of economic action, considering both the human capacity to act as sources of constraint, whose mechanisms are analyzed the structural and political. In methodological terms this is a case study, analyzed from the research literature, documentary and experimental. Primary data were collected through semi-structured interviews and analyzed in depth by the technique of content analysis. Was adopted a longitudinal approach, seeking to understand the phenomenon from the perspective of the subjects, describing it in an inductive process of investigation. After characterizing the sector and defining their technological trajectory, the analysis of the results followed its four stages: (1) Introduction of Technology: 1973-1980, (2) Intensification of Research: 1981-1991, (3) Technological Adaptation, 1992 -2003, (4) Technological Crisis: 2004-2009. A cross-sectional analysis along the evolutionary trajectory revealed the character of structural changes and policies over time, and implications on the generating process of innovation. Note that, the technological limit to which the sector reached requires changes in technology standards, but is more likely that the potiguar shrimp is entering a new phase of his career in technology rather than a new technological paradigm
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The durability of the cellulose-cement composites is a decisive factor to introduce such material in the market. Polymers have been used in concrete and mortar production to increase its durability. The goal of this work was the physical and mechanical characterization of cellulose-cement composites modified by a polymer and the subsequent durability evaluation. The work also evaluated the dispersion of acrylic polymer in composites made of Pinus caribaea residues. The physical properties observed were water absorption by immersion and bulk density. Rupture modulus and toughness were determined by flexural test. The specimens were obtained from pads, produced by pressing and wet curing. Samples were subjected to accelerated aging tests by repeated wetting and drying cycles and hot-water bath and natural aging. The scanning electron microscopy (SEM) allowed verifying the fiber and composite characteristics along the time. For the composite range analyzed, it was observed the polymer improved the mechanical properties of composites besides a significant decreasing in water absorption. The use of polymer improved the performance of vegetable fiber-cement composites when compared to the conventional mortar, due to water absorption decreasing.
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This study examined the influence of three polymerization cycles (1: heat cure - long cycle; 2: heat cure - short cycle; and 3: microwave activation) on the linear dimensions of three denture base resins, immediately after deflasking, and 30 days after storage in distilled water at 37± 2ºC. The acrylic resins used were: Clássico, Lucitone 550 and Acron MC. The first two resins were submitted to all three polymerization cycles, and the Acron MC resin was cured by microwave activation only. The samples had three marks, and dimensions of 65 mm in length, 10 mm in width and 3 mm in thickness. Twenty-one test specimens were fabricated for each combination of resin and cure cycle, and they were submitted to three linear dimensional evaluations for two positions (A and B). The changes were evaluated using a microscope. The results indicated that all acrylic resins, regardless of the cure cycle, showed increased linear dimension after 30 days of storage in water. The composition of the acrylic resin affected the results more than the cure cycles, and the conventional acrylic resin (Lucitone 550 and Clássico) cured by microwave activation presented similar results when compared with the resin specific for microwave activation.
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas . Faculdade de Educação Física
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Universidade Estadual de Campinas. Faculdade de Educação Física
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Removable partial dentures (RPD) demand specific hygienic cleaning and the combination of brushing with immersion in chemical solutions has been the most recommended method for control of biofilm. However, the effect of the cleansers on metallic components has not been widely investigated. This study evaluated the effect of different cleansers on the surface of RPD. Five disc specimens (12 mm x 3 mm metallic disc centered in a 38 x 18 x 4 mm mould filled with resin) were obtained for each experimental situation: 6 solutions [Periogard (PE), Cepacol (CE), Corega Tabs (CT), Medical Interporous (MI), Polident (PO), 0.05% sodium hypochlorite (NaOCl), and distilled water (DW) control] and 2 Co-Cr alloys [DeguDent (DD) and VeraPDI (VPDI)] were used for each experimental situation. A 180-day immersion was simulated and the measurements of roughness (Ra, µm) of metal and resin were analyzed using 2-way ANOVA and Tukey’s test. The surface changes and tarnishes were examined with a scanning electronic microscopy (SEM). In addition, energy dispersive x-ray spectrometry (EDS) analysis was carried out at representative areas. Visually, NaOCl and MI specimens presented surface tarnishes. The roughness of materials was not affected by the solutions (p>0.05). SEM images showed that NaOCl and MI provided surface changes. EDS analysis revealed the presence of oxygen for specimens in contact with both MI and NaOCl solutions, which might suggest that the two solutions promoted the oxidation of the surfaces, thus leading to spot corrosion. Within the limitations of this study, it may be concluded that the NaOCl and MI may not be suitable for cleaning of RPD.
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Prosthetic restorations that have been tried in the patient's mouth are potential sources of infection. In order to avoid cross-infection, protocols for infection control should be established in dental office and laboratory. This study evaluated the antimicrobial efficacy of disinfectants on full metal crowns contaminated with microorganisms. Full crowns cast in a Ni-Cr alloy were assigned to one control group (n=6) and 5 experimental groups (n=18). The crowns were placed in flat-bottom glass balloons and were autoclaved. A microbial suspension of each type of strain - S. aureus, P. aeruginosa, S. mutans, E. faecalis and C. albicans- was aseptically added to each experimental group, the crowns being allowed for contamination during 30 min. The contaminated specimens were placed into recipients with the chemical disinfectants (1% and 2% sodium hypochlorite and 2% glutaraldehyde) for 5, 10 and 15 min. Thereafter, the crowns were placed into tubes containing different broths and incubated at 35ºC. The control specimens were contaminated, immersed in distilled water for 20 min and cultured in Thioglycollate broth at 35ºC. Microbial growth assay was performed by qualitative visual examination after 48 h, 7 and 12 days. Microbial growth was noticed only in the control group. In the experimental groups, turbidity of the broths was not observed, regardless of the strains and immersion intervals, thus indicating absence of microbial growth. In conclusion, all chemical disinfectants were effective in preventing microbial growth onto full metal crowns.
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This study evaluated the color stability, surface roughness and flexural strength of a microwave-polymerized acrylic resin after immersion in sodium hypochlorite (NaOCl), simulating 20 min of disinfection daily during 180 days. Forty disk-shaped (15 x 4 mm) and 40 rectangular (65 x 10 x 3 mm) specimens were prepared with a microwave-polymerized acrylic resin (Onda-Cryl). Specimens were immersed in either 0.5% NaOCl, 1% NaOCl, Clorox/Calgon and distilled water (control). Color measurements were determined by a portable colorimeter. Three parallel lines, separated by 1.0 mm, were registered on each specimen before and after immersion procedures to analyze the surface roughness. The flexural strength was measured using a 3-point bending test in a universal testing machine with a 50 kgf load cell and a crosshead speed of 1 mm/min. Data were analyzed statistically by ANOVA and Tukey's test (?=0.05). There was no statistically significant differences (p>0.05) among the solutions for color, surface roughness and flexural strength. It may be concluded that immersion in NaOCl solutions simulating short-term daily use during 180 days did not influence the color stability, surface roughness and flexural strength of a microwave-polymerized acrylic resin.
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This study evaluated the influence of internal tooth bleaching with 38% hydrogen peroxide (H2O2) on the permeability of the coronal dentin in maxillary anterior teeth and premolars. Seventy teeth (14 per group) were used: central incisors (CI), lateral incisor (LI), canines (C), first premolars (1PM) and second premolars (2PM). Pulp chamber access and transversal sectioning at 2 mm from the cementoenamel junction were performed and the specimens were divided into 2 groups (n= 7): a) no treatment and b) bleaching with 38% H2O2. The bleaching agent was applied to the buccal surface and to the pulp chamber for 10 min. This procedure was repeated 3 times. The specimens were processed histochemically with copper sulfate and rubeanic acid, sectioned longitudinally, and digitalized in a scanner. The area of stained dentin was measured using Image Tool software. Data were analyzed statistically by ANOVA and Tukey's HSD test (?=0.05). There was statistically significant difference (p<0.001) among the untreated groups, CI (0.23 ± 0.26) having the lowest permeability and LI (10.14 ± 1.89) the highest permeability. Among the bleached groups, dentin permeability was increased in all groups of teeth except for 2PM. It may be concluded that bleaching with 38% H2O2 affected dentin permeability near the pulp chamber in maxillary anterior teeth and in first and second premolars.