14 resultados para Accelerating universes

em Universidade Federal do Rio Grande do Norte(UFRN)


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Since the middle 80 s from the 20th century, some musical genres associated to the Brazilian Northeastern region notably the forró, coco de embolada and repente de viola have been gradually incorporated to the musical production of south France linked to the occitanista trend, currently linking many musicians and groups from those regions in both countries. This paper is engaged in reflecting on the particular experience of the groups formed by the Escambiar Association, located on the city of Toulouse, and specially the duet Fabulous Trobadors, whose compositions are mostly made in the coco de embolada form. Watching the motivations and the processes that led to the creation of the groups from this association and it s current operation, this study investigates the transcultural phenomenon, that allow to cross two symbolic universes through rationalizing speeches about music, considering the locality s production in the midst of a political debate that involve questions about cultural identity and tradition

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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective

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Hypertensive syndromes in pregnancy (HSP) are configured as one of the major complications in the pregnancy and postpartum period and can lead premature newborn and subsequent hospitalization of the newborn to the Neonatal Intensive Care Unit (NICU). This study aimed to analyze the perceptions, meanings and feelings of mothers on the hypertensive syndromes in pregnancy and premature obstetric labor. The research was qualitative and has a theoretical methodological the Social Representations Theory(SRT) in the approach to the Central Nucleus Theory. The study included 70 women, mean age 29 years, predominantly school to high school, most of them married or in consensual union, primiparous and prevalence of cesarean delivery occurred between 32 and 37 weeks of pregnancy.The data were collected from may to december 2008 in the Maternity School Januário Cicco in Natal , and obtained through the following instruments for data collection: questionnaire including questions about socio-demographic status; the Free Words Association Test (FWAT) and and verbalized mental image construction used three stimuli: such as pregnancy with high blood pressure, preterm birth and NICU, and interview with the following guiding question: what it meant for you to have a pregnancy with high blood pressure and consequently the birth of a premature baby? Data analysis was performed using multi-method obtained from the data processing by EVOC (Ensemble Programmes Permettant L 'Analyze des Évocations) and ALCESTE (Analyse Lexicale par Contexte d'un Ensemble de Segment de Texte) and thematic analysis in categories. The results will be presented in four thematic units under the following representative universes: HSP, prematurity as a result of HSP, NICU and the social representations of mothers on the hypertensive disorder of pregnancy sequenced premature birth and hospitalization of the child in the NICU. The results obtained by multimethod analyses showed similar constructions and point to death as the central nucleus and negative aspects, coping strategies, need of care, knowledge about the disease, fragility and meanings of the NICU as peripheral elements. It is considered that the perceptions, meanings and feelings of puerperal women in relation to HSPs and to premature delivery are a negative social representation, with representational elements that may have influenced the adverse effects on the disease and its consequences. We suggest action on the peripheral elements of this representation, with adequate orientation, early diagnosis, effective conduct, receptive attitude on the part of the team, health promotion measures and effective public policies, in order to improve the care provided to puerperal women, making them feel welcome and minimizing their suffering

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This thesis is resulted of a research on propagated the social representations of constructivism in the Internet, which as had estimated basic the idea of Moscovici (1961) of that the media it has determinative paper in the popularization of the scientific theories, in formation e propagation of the social representations and in the construction of behaviors human beings. Understanding the Internet as latest space of circulation of social communications, therefore, privileged field (and still not explored) for studies of social representations, we choose this half midiático as investigative field of our research, it if it constitutes in the "great ocean of the new informational planet" (LEVY, 2000, p. 126), besides making possible the interaction with different forms of images, different individuals, different ' world ', configuring itself as important space of symbolic production e of analysis of the representational process in the world contemporary. Based in these questions, we trace as objective to analyze the circulating speech propagated on-line on the constructivism, searching to apprehend the social representations shared the respect. This objective was constructed in face of the insertion of the theory constructivist in the educational way has two decades more than, as well as of its consolidation as reference in different social contexts, mainly in midiático. The question that directed the research was: as this theory obtains to penetrate in some layers of our society, to influence the world readings e the behaviors of different people? That modifications it suffers in this trajectory and which the paper of the Internet in this process? The corpus of the research was constituted of the substances on the theory found in the Internet, in pages in Portuguese of Google, in the period of 27 of July of 2004 the 17 of August of 2004. The data they had been analyzed on the basis of the project of analysis of content elaborated for Moscovici (1961) and in the estimated theoreticians of the social communication, in special of the hypermedia. The results had disclosed that the Internet participates of determinative form in the process of popularization of the constructivism theory, not only spreading out its estimated theoretician- methodological for the domain public (diffusion), but propagating positive beliefs and images of its postulates (propagation) and using them it service of interests politicians e financiers (propaganda). The popularization of the constructivism in the Internet and social representations of this theory propagated configure one process in which the theory passes of pedagogical theoretical landmark for grief, assuming a commercial character extremely and the status of solution for problems of the education and the society, stirring up attitudes and behaviors in public, most general possible, that comes to take care of to the interests politicians e marketing. Recognizing the diversity, the permanent renewal of information and the negotiation of directions gifts in the Internet, as well as the innumerable ones forms of access to the information found by it, we consider results of the research as fruits of the inherent characteristics to this way midiático, to the time where we call the attention for relativity these results, for the plasticity of knowing them and sensible propagated on-line e for the great challenge that the hypermedia imposes to the study of communication phenomena, of the social representations and in educational quarrels and for the necessity of new research that they investigate the forms of socialization of the information and communication propitiated by hypermedia and its implications in the construction of the symbolic universes and in practical social

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The present study had the objective to identify to the Social Representations of the professionals of medicine and nursing superior level of the Program Health of the Family concerning the assistance for the gestation. The research was qualitative under the optics of the Theory of the Social Representations of Serge Moscovici, of the Central Nucleus of Jean-Claude Abric and of the Analysis of Content of Laurence Bardin. We worked with the following instruments for the collection of data: Questionnaires, with social-demographic data; Free association of Words, with the inductive terms Pregnancy, Assistance for Gestation and Care; Production of mental image and half-structuralized Interview, with the following question: What does the assistance for the gestation represent for you? . We interviewed all the professionals of nursing and medicine of the Program Health of the Family in the city of Santa Cruz /RN (ten for each profession) in the period of February and March of 2007. From the analysis of the social-demographics data, we respectively identified the following percentages for nursing and medicine: the feminine sex for nursing predominated (90%); the age between 24 and 33 (70 and 60%); the religion catholic (80 and 50%) and 50% of the two groups has up to two years of formation and work in the score of the research. The analysis of the others instruments resulted in two categories: Institutionalized vision and Vision of the Common-sense. In the free association of words, the category institutionalized vision is configured as Central Nucleus and of the common sense one as nucleus Peripheral, demonstrating that the Social Representations of the assistance for the gestation attendance are in the universes consensual. In the mental images, we identified to this same construction. In the content of the interviews, the institutionalized vision is permeated by the responsibility of making and the availability of having - assistance for the gestation is recommended by the Health department and necessary genders - while the vision of the common-sense can be represented by the category sort, whose role of professionals of the assistance for the gestation is to strengthen the responsibility for the woman of a maternity socially constructed. In short, the analyzed speeches reflect that, to the knowledge acquired in the academy, are incorporated in the knowledge of the daily professional, and conducted by popular myths. Medicine and nursing recognize the importance of the attendance in such a way for the chance to educate the women for the maternity as for the possibility to prevent complications, but in its speeches they had excluded from this process the masculine figure. We conclude that the meaning of the inductive term take care, part of the common-sense and is incorporated the institutionalized speech to humanize the assistance. However, the pregnancy ceases from being seen in its natural biological direction and starts to be analyzed as a moment of fragility and predisposition the illnesses. Finally, the social nursing and the central nucleus representations for the assistance in gestation for medicine is anchored in the speeches institutionalized and of the common-sense, reflecting the concern in establishing a humanized assistance with quality

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This study aims to analyze social representations of elders to their fragile situation at home, with the presence of one or more characteristics, as defined by the Brazilian Ministry of Health. It is a descriptive and qualitative study, based on methodological -principles of the Theory of Social Representations. Setting was the homes of elderly residents in the area ascribed to a Family Health Unit (FHU) in the city of Natal. A total of 10 elderly subjects, whose choice was intentional and according to the need for USF home visit in a period of time, considering the saturation process of the information. As collection procedures were used the semi-structured interview and participant observation in accordance with the ethical rules of Resolution No. 196/96, with the assent of the Ethics and Research UFRN. To analyze the results, it was used the thematic content analysis in the aspect of preparation of representations, focusing on the totality of the discourse of the subjects. The results indicate that most study participants felt difficult to give meaning to the terms weakness and to be weak, although many present one or more aspects of the syndrome of frailty. From the content analysis of participants speeches in this study, we achieved the following categories: fragility as illness and disease as aging, aging and frailty as causes of changes and difficulties in daily life, the presence of family life in the fragile elderly, fragility as weakness and the risk for falls, the perception of being weak like a different person in addition to the absence of fragility in elderly life. Thus, through the processes of anchoring and objectification, the "fragile being" became familiar and concrete, showing that the meaning of weakness, besides the scientific definition found in the reified universes, can be reinterpreted and built within the consensus universes. About the care received by the staff of Family Health, from the viewpoint of older people there seems to be an understanding about the role of professional nurses; on the other hand, older people often mention the role of the Community Health Agent

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A challenge that remains in the robotics field is how to make a robot to react in real time to visual stimulus. Traditional computer vision algorithms used to overcome this problem are still very expensive taking too long when using common computer processors. Very simple algorithms like image filtering or even mathematical morphology operations may take too long. Researchers have implemented image processing algorithms in high parallelism hardware devices in order to cut down the time spent in the algorithms processing, with good results. By using hardware implemented image processing techniques and a platform oriented system that uses the Nios II Processor we propose an approach that uses the hardware processing and event based programming to simplify the vision based systems while at the same time accelerating some parts of the used algorithms

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Recent astronomical observations (involving supernovae type Ia, cosmic background radiation anisotropy and galaxy clusters probes) have provided strong evidence that the observed universe is described by an accelerating, flat model whose space-time properties can be represented by the FriedmannRobertsonWalker (FRW) metric. However, the nature of the substance or mechanism behind the current cosmic acceleration remains unknown and its determination constitutes a challenging problem for modern cosmology. In the general relativistic description, an accelerat ing regime is usually obtained by assuming the existence of an exotic energy component endowed with negative pressure, called dark energy, which is usually represented by a cosmological constant ¤ associated to the vacuum energy density. All observational data available so far are in good agreement with the concordance cosmic ¤CDM model. Nevertheless, such models are plagued with several problems thereby inspiring many authors to propose alternative candidates in the relativistic context. In this thesis, a new kind of accelerating flat model with no dark energy and fully dominated by cold dark matter (CDM) is proposed. The number of CDM particles is not conserved and the present accelerating stage is a consequence of the negative pressure describing the irreversible process of gravitational particle creation. In order to have a transition from a decelerating to an accelerating regime at low redshifts, the matter creation rate proposed here depends on 2 parameters (y and ߯): the first one identifies a constant term of the order of H0 and the second one describes a time variation proportional to he Hubble parameter H(t). In this scenario, H0 does not need to be small in order to solve the age problem and the transition happens even if there is no matter creation during the radiation and part of the matter dominated phase (when the ß term is negligible). Like in flat ACDM scenarios, the dimming of distant type Ia supernovae can be fitted with just one free parameter, and the coincidence problem plaguing the models driven by the cosmological constant. ACDM is absent. The limits endowed with with the existence of the quasar APM 08279+5255, located at z = 3:91 and with an estimated ages between 2 and 3 Gyr are also investigated. In the simplest case (ß = 0), the model is compatible with the existence of the quasar for y > 0:56 whether the age of the quasar is 2.0 Gyr. For 3 Gyr the limit derived is y > 0:72. New limits for the formation redshift of the quasar are also established

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The recent astronomical observations indicate that the universe has null spatial curvature, is accelerating and its matter-energy content is composed by circa 30% of matter (baryons + dark matter) and 70% of dark energy, a relativistic component with negative pressure. However, in order to built more realistic models it is necessary to consider the evolution of small density perturbations for explaining the richness of observed structures in the scale of galaxies and clusters of galaxies. The structure formation process was pioneering described by Press and Schechter (PS) in 1974, by means of the galaxy cluster mass function. The PS formalism establishes a Gaussian distribution for the primordial density perturbation field. Besides a serious normalization problem, such an approach does not explain the recent cluster X-ray data, and it is also in disagreement with the most up-to-date computational simulations. In this thesis, we discuss several applications of the nonextensive q-statistics (non-Gaussian), proposed in 1988 by C. Tsallis, with special emphasis in the cosmological process of the large structure formation. Initially, we investigate the statistics of the primordial fluctuation field of the density contrast, since the most recent data from the Wilkinson Microwave Anisotropy Probe (WMAP) indicates a deviation from gaussianity. We assume that such deviations may be described by the nonextensive statistics, because it reduces to the Gaussian distribution in the limit of the free parameter q = 1, thereby allowing a direct comparison with the standard theory. We study its application for a galaxy cluster catalog based on the ROSAT All-Sky Survey (hereafter HIFLUGCS). We conclude that the standard Gaussian model applied to HIFLUGCS does not agree with the most recent data independently obtained by WMAP. Using the nonextensive statistics, we obtain values much more aligned with WMAP results. We also demonstrate that the Burr distribution corrects the normalization problem. The cluster mass function formalism was also investigated in the presence of the dark energy. In this case, constraints over several cosmic parameters was also obtained. The nonextensive statistics was implemented yet in 2 distinct problems: (i) the plasma probe and (ii) in the Bremsstrahlung radiation description (the primary radiation from X-ray clusters); a problem of considerable interest in astrophysics. In another line of development, by using supernova data and the gas mass fraction from galaxy clusters, we discuss a redshift variation of the equation of state parameter, by considering two distinct expansions. An interesting aspect of this work is that the results do not need a prior in the mass parameter, as usually occurs in analyzes involving only supernovae data.Finally, we obtain a new estimate of the Hubble parameter, through a joint analysis involving the Sunyaev-Zeldovich effect (SZE), the X-ray data from galaxy clusters and the baryon acoustic oscillations. We show that the degeneracy of the observational data with respect to the mass parameter is broken when the signature of the baryon acoustic oscillations as given by the Sloan Digital Sky Survey (SDSS) catalog is considered. Our analysis, based on the SZE/X-ray data for a sample of 25 galaxy clusters with triaxial morphology, yields a Hubble parameter in good agreement with the independent studies, provided by the Hubble Space Telescope project and the recent estimates of the WMAP

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Biodiesel production has increased over the last decade because of the benefits associated with this fuel, including renewability, domestic feedstock, lower toxicity, and biodegradability. From 2008, the use of beef tallow as a feedstock for biodiesel production in Brazil has increased in significance, representing the second largest source of biodiesel, after soybeans. However, the performance of biodiesel in cold weather conditions is worse than diesel because of deposition of insoluble at low temperatures, accelerating the plugging of fuel filters and injectors of the vehicle engine. Studies have been conducted on beef tallow biodiesel, mostly related to the properties of thermal and oxidative stability. However, few studies have described the nature of the precipitate formed and its influence on product quality. Research suggests that the cause of deposition is related to the nature of saturated esters and monoacylglycerols as inducing agents. This study monitored the levels of mono-, diand triacylglycerols, the oxidation stability and the cold filter plugging point (CFPP) in beef tallow biodiesel samples from two commercial producers in Brazil for a period of twelve months. Filtered precipitates were analyzed by comparative techniques of GCFID, HPLC-UV/VIS, HPLC-MS-IT-TOF and TG to verify the nature, using monopalmitin and monostearin as reference standards. The formation of precipitate reduced the levels of monoacylglycerols in the beef tallow biodiesel. GC-FID and LCMS- IT-TOF results confirmed the nature of the deposit as saturated monoacylglycerols, predominantly monostearin and monopalmitin as the second major component. Moreover the TG analysis of the residue indicated similar thermal decomposition of the reference standards. The precipitate did not affect the oxidation stability of beef tallow biodiesel and the CFPP characteristic of blends up B60. However, the presence of iron reduced significantly the oxidation stability of biodiesel

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Biodiesel production has increased over the last decade because of the benefits associated with this fuel, including renewability, domestic feedstock, lower toxicity, and biodegradability. From 2008, the use of beef tallow as a feedstock for biodiesel production in Brazil has increased in significance, representing the second largest source of biodiesel, after soybeans. However, the performance of biodiesel in cold weather conditions is worse than diesel because of deposition of insoluble at low temperatures, accelerating the plugging of fuel filters and injectors of the vehicle engine. Studies have been conducted on beef tallow biodiesel, mostly related to the properties of thermal and oxidative stability. However, few studies have described the nature of the precipitate formed and its influence on product quality. Research suggests that the cause of deposition is related to the nature of saturated esters and monoacylglycerols as inducing agents. This study monitored the levels of mono-, diand triacylglycerols, the oxidation stability and the cold filter plugging point (CFPP) in beef tallow biodiesel samples from two commercial producers in Brazil for a period of twelve months. Filtered precipitates were analyzed by comparative techniques of GCFID, HPLC-UV/VIS, HPLC-MS-IT-TOF and TG to verify the nature, using monopalmitin and monostearin as reference standards. The formation of precipitate reduced the levels of monoacylglycerols in the beef tallow biodiesel. GC-FID and LCMS- IT-TOF results confirmed the nature of the deposit as saturated monoacylglycerols, predominantly monostearin and monopalmitin as the second major component. Moreover the TG analysis of the residue indicated similar thermal decomposition of the reference standards. The precipitate did not affect the oxidation stability of beef tallow biodiesel and the CFPP characteristic of blends up B60. However, the presence of iron reduced significantly the oxidation stability of biodiesel

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Compatibility testing between a drilling fluid and a cement slurry is one of the steps before an operation of cementing oil wells. This test allows us to evaluate the main effects that contamination of these two fluids may cause the technological properties of a cement paste. The interactions between cement paste and drilling fluid, because its different chemical compositions, may affect the cement hydration reactions, damaging the cementing operation. Thus, we carried out the study of the compatibility of non-aqueous drilling fluid and a cement slurry additives. The preparation procedures of the non-aqueous drilling fluid, the cement paste and completion of compatibility testing were performed as set out by the oil industry standards. In the compatibility test is evaluated rheological properties, thickening time, stability and compressive strength of cement pastes. We also conducted analyzes of scanning electron microscopy and X-ray diffraction of the mixture obtained by the compatibility test to determine the microstructural changes in cement pastes. The compatibility test showed no visual changes in the properties of the cement paste, as phase separation. However, after the addition of nonaqueous drilling fluid to cement slurry there was an increased amount of plastic viscosity, the yield point and gel strength. Among the major causative factors can include: chemical reaction of the components present in the non-aqueous drilling fluid as the primary emulsifier, wetting agent and paraffin oil, with the chemical constituents of the cement. There was a reduction in the compressive strength of the cement paste after mixing with this drilling fluid. Thickening test showed that the oil wetting agent and high salinity of the non-aqueous fluid have accelerating action of the handle of the cement paste time. The stability of the cement paste is impaired to the extent that there is increased contamination of the cement slurry with the nonaqueous fluid. The X-ray diffraction identified the formation of portlandite and calcium silicate in contaminated samples. The scanning electron microscopy confirmed the development of the identified structures in the X-ray diffraction and also found the presence of wells in the cured cement paste. The latter, formed by the emulsion stability of the drilling fluid in the cement paste, corroborate the reduction of mechanical strength. The oil wetting agent component of the non-aqueous drilling fluid, the modified cement hydration processes, mainly affecting the setting time.

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Since the middle 80 s from the 20th century, some musical genres associated to the Brazilian Northeastern region notably the forró, coco de embolada and repente de viola have been gradually incorporated to the musical production of south France linked to the occitanista trend, currently linking many musicians and groups from those regions in both countries. This paper is engaged in reflecting on the particular experience of the groups formed by the Escambiar Association, located on the city of Toulouse, and specially the duet Fabulous Trobadors, whose compositions are mostly made in the coco de embolada form. Watching the motivations and the processes that led to the creation of the groups from this association and it s current operation, this study investigates the transcultural phenomenon, that allow to cross two symbolic universes through rationalizing speeches about music, considering the locality s production in the midst of a political debate that involve questions about cultural identity and tradition

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The biofilms microbial forms of association are responsible for generating, accelerating and / or induce the process of corrosion. The damage generated in the petroleum industry for this type of corrosion is significatives, representing major investment for your control. The aim of this study was to evaluate such tests antibiograms the effects of extracts of Jatropha curcas and essential oil of Lippia gracilis Schauer on microrganisms isolated from water samples and, thereafter, select the most effective natural product for further evaluation of biofilms formed in dynamic system. Extracts of J. curcas were not efficient on the complete inhibition of microbial growth in tests type antibiogram, and essential oil of L. gracilis Schauer most effective and determined for the other tests. A standard concentration of essential oil of 20 μL was chosen and established for the evaluation of the biofilms and the rate of corrosion. The biocide effect was determined by microbial counts of five types of microorganisms: aerobic bacteria, precipitating iron, total anaerobic, sulphate reducers (BRS) and fungi. The rate of corrosion was measured by loss of mass. Molecular identification and scanning electron microscopy (SEM) were performed. The data showed reduction to zero of the most probable number (MPN) of bacteria precipitating iron and BRS from 115 and 113 minutes of contact, respectively. There was also inhibited in fungi, reducing to zero the rate of colony-forming units (CFU) from 74 minutes of exposure. However, for aerobic and anaerobic bacteria there was no significant difference in the time of exposure to the essential oil, remaining constant. The rate of corrosion was also influenced by the presence of oil. The essential oil of L. gracilis was shown to be potentially effective