15 resultados para Confinement

em Universidade Federal do Rio Grande do Norte(UFRN)


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Leachates are effluent produced by decomposition of solid waste, they have complex composition and can be highly toxic. Therefore such percolated liquid should be collected and treated properly to avoid environmental contamination of soil and of water bodies. The objective of this study was to evaluate the toxicity through ecotoxicological tests with Ceriodaphnia dubia (Cladocera - Crustacea) of percolated liquids generated in two different systems of municipal solid waste (MSW) disposal in the city of Natal/ RN: A Sanitary Landfill in the Metropolitan Region of Natal/ RN, and in a dump off area. Furthermore, it was evaluated the possible contamination of the underground water of the dump off area. Two monthly samples were taken at four points between the months of May/2009 and January/2010. The Point "A" corresponds to the end of the pond leachate treatment in ASRMN; The Point "B" corresponds to a containment pond at the dump. The Point "C" is an area near one of the cells of the dump off area where the leachate outcrops; The Point "D" stands for an underground water well at the area. The last point, called "E" was sampled only once and corresponds to the slurry produced by temporary accumulation of solid waste in the open area of the dump. The ecotoxicological tests, acute and chronic, followed the ABNT 13373/2005 rules, with some modifications. The samples were characterized by measuring the pH number, the dissolved oxygen (DO), the salinity, BOD5, COD, Cd, Cu, Pb, Cr, Fe, Mg, Ni, and Zn. At Point A, the average number of EC50-48h ranged between 1.0% and 2.77% (v/v), showing a high toxicity of the leachate to C.dubia in all months. To this point, positive correlations were found between the EC50- 48 with precipitation. Negative correlations were found between the EC50- 48h with salinity. At point B there was no response of the acute exposure of organisms to the test samples. At point C the EC50-48h ranged from 17.68% to 35.36% in just two months of the five ones analyzed, not correlated meaning. Point D, the EC50-48h level ranged between 12.31% and 71.27%, showed a negative correlation with, only, precipitation. Although it was observed toxicity of underground water in the Landfill Area, there was no evidence of water contamination by leachate, however, due to the toxic character of this water, additional tests should be conducted to confirm the quality of water that is used for human supply. At point E there was no acute toxicity. These results support the dangers of inappropriate disposal of MSW to water bodies due to the high toxicity of the leachate produced highlighting the necessity of places of safe confinement and a treatment system more effective to it

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Due to the occurrence of diseases in the use of structural reinforcements in composites, with presentation of concrete blanket detachment, has been identified the need to evaluate the performance of concrete reinforced with glass fiber. This study aims to evaluate these concretes by means of testing methodologies, using concrete with low resistance with structural reinforcement for confinement by preimpregnated glass fiber and traditional fiberglass blanket. The first stage of work was the development of methodologies for analysis, opting for four types, such as the acoustic survey, strength to compressive, the pull-off and ultrasound. Next, tests were carried out using the four selected methodologies in 30 of proof-of-specimens by 5x10 cm, 15 were reinforced with the traditional fiberglass blanket with 5specimens exposed to test a marine environment of marine coastline of Natal-RN and 15 were reinforced with a pre-impregnated glass fiber blanket, as well as 5specimens exposed to a test environment of the marine coastline of Natal-RN. After conducting the acoustic survey, it has been verified a lack of delaminating and air bubbles in the samples, confirming the absence of gross shortcomings in the implementation of the ribs both the traditional fiberglass blanket and in the preimpregnated fiber glass blanket. After carrying out methods of pull-off and compressive strengthening test it was observed that the reinforced proof-bodies with pre-impregnated glass blanket showed maximum stresses higher than the traditional fiberglass blanket; consequently a greater grip with the formation of a smaller area of . fracture, unlike traditional glass mat, which showed lower maximum stresses, with a greater area of fracture. It was also found that the traditional fiberglass blanket presented detachment of blanket-concrete interface, unlike the pre-impregnated fiberglass blanket, which showed a better grip on the blanket-concrete interface. In the trial of ultrasound there was no presence of cracks in the blanket-concrete interface, yielding to both blankets good compactness of the concrete. At the end of this work, they were developed and proposed two methods of testing for evaluation of reinforced concrete structures with composites, for standardization, the acoustic survey and pull-off

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Hansen's disease, despite significant advances regarding the diagnosis, treatment and control still carries an immense burden of stigma as a result, mainly of its socio-historical marked by prejudice and isolation of patients, translated by suffering, abandonment and psychosocial problems. Thus, the study set out to rescue the life stories of former leprosy patients with a leprosarium history; recovering the life trajectory stories of these former patients and to identify common factors to these life stories. Exploratory-descriptive study with a qualitative approach, using the Life History Research Methodology. The sample was composed by twelve former leprosy patients who lived while undergone treatment in the Colony Hospital St. Francisco de Assis, located in Natal, Rio Grande do Norte. The network was composed without considering sex and age limit, patients that lived in the Colony Hospital for at least six months and who agree to participate freely in the study. The subjects with special physical needs (hearing) or mental disabilities and those who do not agree to participate were excluded. A semi-structured interview was used to data collection, the interviews were recorded in the household context of individual, residents in neighborhoods Felipe Camarão, Km 6 and Jardim America, more precisely at Nova Vida village, all located in that district. The data collected were subjected to the technique of thematic content analysis. This study had obtained an appropriate consent of the UFRN Research Ethics Committee under the protocol No. 016/2010. After extensive and careful readings of life stories we identified three themes that guided the data analysis: behavioral stages, social exclusion and, stigma and prejudice. Thus, it is clear that the practice of compulsory confinement of patients in nursing homes and the mythical image of Hansen's disease as being ugly and deformed, contributed to solidifying the historical stigma surrounding the disease and its patients, raising in society and family attitudes and feelings of exclusion, prejudice and fear. Moreover, there are remarkable stories in the lives of these interviewed reporting suffering, denials, anger that reverberate to this day, affecting negatively the social and family reintegration of these individuals. As a result, we see the need for managers and local health professionals, especially nurses, rethink existing strategies for social rehabilitation of the patient and ex-leprosy patient aiming to suppression unjust and harmful stigma rooted in image and stories of these individuals

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Leprosy as a public health problem , there is still quite some time , even with treatment for decades . Your health-disease process is marked by a historical backdrop of stigma , prejudice, social exclusion and authoritarian decisionducts , in order to extinguish the disease milieu under the regime of compulsory confinement of the patient. In this perspective , the Brazilian public health twentieth century adopted policies of compulsory isolation , which meant that those who receive a diagnosis of leprosy were isolated from society and their families in hospitals colonies . Objective is, to the study, rescue the trajectory of health professionals in the Colony Hospital St. Francis of Assisi , in Natal / RN ; Identify the policy was perceived as compulsory institutionalization imposed for leprosy patients by health professionals ; describe the behaviors Professional Hospital adopted in Cologne ; Retrieve information about the existence and functioning of the Hospital and Create a documentary of historical fragments of leprosy from the point of view of professionals from a former colony. Exploratory - descriptive method with a qualitative approach , using the methodological framework thematic oral history was used . Obtained approval by the IRB of the Federal University of Rio Grande do Norte, under Protocol No 461 403 and CAAE 19476913.9.0000.5537 . Be interviewed during the period of November and December 2013 , five health professionals who worked in the hospital colony , using audio recorder and images to capture and record the statements. The interviews were transcribed , textualized, transcriadas and sent to reviewers to step conference of the reports. Subsequently , analysis of the stories was made from the proposed content analysis of Bardin . The results and discussion are presented in the form of article: Opinion of nursing professionals who worked in a hospital for leprosy colony , which aimed to : identify the opinion of nurses who worked in hospital colony on the lives of patients . In this article, three main themes were highlighted and discussed from the reports of colaboradoes : I - The socialization process of internal II - 16 Prejudice , stigma and discrimination III - Social exclusion versus inclusion . We conclude that , in the context of the colony hospital, the performance of health professionals contributed significantly to that stigma , prejudice and social exclusion would be minimized and that the experience of asylum seekers in the colony were not seen more traumatic

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We have used ab initio calculations to investigate the electronic structure of SiGe based nanocrystals (NC s). This work is divided in three parts. In the first one, we focus the excitonic properties of Si(core)/Ge(shell) and Ge(core)/Si(shell) nanocrystals. We also estimate the changes induced by the effect of strain the electronic structure. We show that Ge/Si (Si/Ge) NC s exhibits type II confinement in the conduction (valence) band. The estimated potential barriers for electrons and holes are 0.16 eV (0.34 eV) and 0.64 eV (0.62 eV) for Si/Ge (Ge/Si) NC s. In contradiction to the expected long recombination lifetimes in type II systems, we found that the recombination lifetime of Ge/Si NC s (τR = 13.39μs) is more than one order of magnitude faster than in Si/Ge NC s (τR = 191.84μs). In the second part, we investigate alloyed Si1−xGex NC s in which Ge atoms are randomly positioned. We show that the optical gaps and electron-hole binding energies decrease linearly with x, while the exciton exchange energy increases with x due to the increase of the spatial extent of the electron and hole wave functions. This also increases the electron-hole wave functions overlap, leading to recombination lifetimes that are very sensitive to the Ge content. Finally, we investigate the radiative transitions in Pand B-doped Si nanocrystals. Our NC sizes range between 1.4 and 1.8 nm of diameters. Using a three-levels model, we show that the radiative lifetimes and oscillator strengths of the transitions between the conduction and the impurity bands, as well as the transitions between the impurity and the valence bands are strongly affected by the impurity position. On the other hand, the direct conduction-to-valence band decay is practically unchanged due to the presence of the impurity

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There is presently a worldwide interest in artificial magnetic systems which guide research activities in universities and companies. Thin films and multilayers have a central role, revealing new magnetic phases which often lead to breakthroughs and new technology standards, never thought otherwise. Surface and confinement effects cause large impact in the magnetic phases of magnetic materials with bulk spatially periodic patterns. New magnetic phases are expected to form in thin film thicknesses comparable to the length of the intrinsic bulk magnetic unit cell. Helimagnetic materials are prototypes in this respect, since the bulk magnetic phases consist in periodic patterns with the length of the helical pitch. In this thesis we study the magnetic phases of thin rare-earth films, with surfaces oriented along the (002) direction. The thesis includes the investigation of the magnetic phases of thin Dy and Ho films, as well as the thermal hysteresis cycles of Dy thin films. The investigation of the thermal hysteresis cycles of thin Dy films has been done in collaboration with the Laboratory of Magnetic Materials of the University of Texas, at Arlington. The theoretical modeling is based on a self-consistent theory developed by the Group of Magnetism of UFRN. Contributions from the first and second neighbors exchange energy, from the anisotropy energy and the Zeeman energy are calculated in a set of nonequivalent magnetic ions, and the equilibrium magnetic phases, from the Curie temperature up to the Nèel temperature, are determined in a self-consistent manner, resulting in a vanishing torque in the magnetic ions at all planes across the thin film. Our results reproduce the known isothermal and iso-field curves of bulk Dy and Ho, and the known spin-slip phases of Ho, and indicate that: (i) the confinement in thin films leads to a new magnetic phase, with alternate helicity, which leads to the measured thermal hysteresis of Dy ultrathin films, with thicknesses ranging from 4 nm to 16 nm; (ii) thin Dy films have anisotropy dominated surface lock-in phases, with alignment of surface spins along the anisotropy easy axis directions, similar to the known spin-slip phases of Ho ( which form in the bulk and are commensurate to the crystal lattice); and (iii) the confinement in thin films change considerably the spin-slip patterns of Ho.

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The effect of confinement on the magnetic structure of vortices of dipolar coupled ferromagnetic nanoelements is an issue of current interest, not only for academic reasons, but also for the potential impact in a number of promising applications. Most applications, such as nano-oscillators for wireless data transmission, benefit from the possibility of tailoring the vortex core magnetic pattern. We report a theoretical study of vortex nucleation in pairs of coaxial iron and Permalloy cylinders, with diameters ranging from 21nm to 150nm, and 12nm and 21nm thicknesses, separated by a non-magnetic layer. 12nm thick iron and Permalloy isolated (single) cylinders do not hold a vortex, and 21nm isolated cylinders hold a vortex. Our results indicate that one may tailor the magnetic structure of the vortices, and the relative chirality, by selecting the thickness of the non-magnetic spacer and the values of the cylinders diameters and thicknesses. Also, the dipolar interaction may induce vortex formation in pairs of 12nm thick nanocylinders and inhibit the formation of vortices in pairs of 21nm thick nanocylinders. These new phases are formed according to the value of the distance between the cylinderes. Furthermore, we show that the preparation route may control relative chirality and polarity of the vortex pair. For instance: by saturating a pair of Fe 81nm diameter, 21nm thickness cylinders, along the crystalline anisotropy direction, a pair of 36nm core diameter vortices, with same chirality and polarity is prepared. By saturating along the perpendicular direction, one prepares a 30nm diameter core vortex pair, with opposite chirality and opposite polarity. We also present a theoretical discussion of the impact of vortices on the thermal hysteresis of a pair of interface biased elliptical iron nanoelements, separated by an ultrathin nonmagnetic insulating layer. We have found that iron nanoelements exchange coupled to a noncompensated NiO substrate, display thermal hysteresis at room temperature, well below the iron Curie temperature. The thermal hysteresis consists in different sequences of magnetic states in the heating and cooling branches of a thermal loop, and originates in the thermal reduction of the interface field, and on the rearrangements of the magnetic structure at high temperatures, 5 produce by the strong dipolar coupling. The width of the thermal hysteresis varies from 500 K to 100 K for lateral dimensions of 125 nm x 65 nm and 145 nm x 65 nm. We focus on the thermal effects on two particular states: the antiparallel state, which has, at low temperatures, the interface biased nanoelement with the magnetization aligned with the interface field and the second nanoelement aligned opposite to the interface field; and in the parallel state, which has both nanoelements with the magnetization aligned with the interface field at low temperatures. We show that the dipolar interaction leads to enhanced thermal stability of the antiparallel state, and reduces the thermal stability of the parallel state. These states are the key phases in the application of pairs of ferromagnetic nanoelements, separated by a thin insulating layer, for tunneling magnetic memory cells. We have found that for a pair of 125nm x 65nm nanoelements, separated by 1.1nm, and low temperature interface field strength of 5.88kOe, the low temperature state (T = 100K) consists of a pair of nearly parallel buckle-states. This low temperature phase is kept with minor changes up to T= 249 K when the magnetization is reduced to 50% of the low temperature value due to nucleation of a vortex centered around the middle of the free surface nanoelement. By further increasing the temperature, there is another small change in the magnetization due to vortex motion. Apart from minor changes in the vortex position, the high temperature vortex state remains stable, in the cooling branch, down to low temperatures. We note that wide loop thermal hysteresis may pose limits on the design of tunneling magnetic memory cells

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In this work we study the spectrum (bulk and surface modes) of exciton-polaritons in infinite and semi-infinite binary superlattices (such as, ···ABABA···), where the semiconductor medium (A), whose dielectric function depends on the frequency and the wavevector, alternating with a standard dielectric medium B. Here the medium A will be modeled by a nitride III-V semiconductor whose main characteristic is a wide-direct energy gap Eg. In particular, we consider the numerical values of gallium nitride (GaN) with a crystal structure wurtzite type. The transfer-matrix formalism is used to find the exciton-polariton dispersion relation. The results are obtained for both s (TE mode: transverse electric) and p (TM mode: transverse magnetic) polarizations, using three diferent kind of additional boundary conditions (ABC1, 2 e 3) besides the standard Maxwell's boundary conditions. Moreover, we investigate the behavior of the exciton-polariton modes for diferent ratios of the thickness of the two alternating materials forming the superlattice. The spectrums shows a confinement of the exciton-polariton modes due to the geometry of the superlattice. The method of Attenuated Total Reflection (ATR) and Raman scattering are the most adequate for probing this excitations

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The physical properties and the excitations spectrum in oxides and semiconductors materials are presented in this work, whose the first part presents a study on the confinement of optical phonons in artificial systems based on III-V nitrides, grown in periodic and quasiperiodic forms. The second part of this work describes the Ab initio calculations which were carried out to obtain the optoeletronic properties of Calcium Oxide (CaO) and Calcium Carbonate (CaCO3) crystals. For periodic and quasi-periodic superlattices, we present some dynamical properties related to confined optical phonons (bulk and surface), obtained through simple theories, such as the dielectric continuous model, and using techniques such as the transfer-matrix method. The localization character of confined optical phonon modes, the magnitude of the bands in the spectrum and the power laws of these structures are presented as functions of the generation number of sequence. The ab initio calculations have been carried out using the CASTEP software (Cambridge Total Sequential Energy Package), and they were based on ultrasoft-like pseudopotentials and Density Functional Theory (DFT). Two di®erent geometry optimizations have been e®ectuated for CaO crystals and CaCO3 polymorphs, according to LDA (local density approximation) and GGA (generalized gradient approximation) approaches, determining several properties, e. g. lattice parameters, bond length, electrons density, energy band structures, electrons density of states, e®ective masses and optical properties, such as dielectric constant, absorption, re°ectivity, conductivity and refractive index. Those results were employed to investigate the confinement of excitons in spherical Si@CaCO3 and CaCO3@SiO2 quantum dots and in calcium carbonate nanoparticles, and were also employed in investigations of the photoluminescence spectra of CaCO3 crystal

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The intention of the present study was to analyze the adequacy of the playground of elementary schools, according to the point of view of the child student, direct user of this type of environment, what estimated its critical in respect to these spaces and aimed at to contribute for its improvement. Many studies have analyzed the quality of the physical environment available for activities of leisure in specific places for children, focusing in the influence of the physical space in the interpersonal relationships and the comfort and satisfaction generated by the physical characteristics of these spaces. Concern with scholar environment, specially the interest on playgrounds, has been subject of recent studies; however, little attention has been given to the opinion of the user-child in relation to this school environment. In this inquiry of the playground of two state schools of 1ª to 4ª series of elementary school in the city of Piracicaba, SP, was used: assystematics observations, photographic register of the studied environments, interviews with child-users and behavioral mapping. The main subjects resulting from the analysis of the interviews content were: adaptation, density and interpersonal relationships, and infantile confinement. The results revealed the unsatisfactory conditions of the courtyards, in respect to person-environment relationship. The children demonstrated to be critical, creative and responsible when answering questions related to the quality of the school courtyard. This finding confirms previous studies and leads to the conclusion that the child, as the direct user, should be included as an excellent source of consultation in the planning of the constructed environment

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This study emerges and develops, from a note by Italo Calvino, who in his novel Invisible Cities advised to avoid saying "that sometimes different cities follow on the same site and with the same name, born and die without knowing, without communication among itself ". The research with a transdisciplinary work ( using elements of sociology, anthropology, geography and communication) made a reflection about segregation and tourism: poverty-richness, center-periphery, tradition- spectaclezation , the visitor-visited maping the touristic circuit and discussing about the phenomenon on the real city and touristic place: Natal and the "Sun City" - Rio Grande do Norte, studying videos produced by residents (documentary) and tourists ( posted on the Internet). Doing a comparative analysis between the realities of these two subjects (resident and tourist), the research found few similarities, many differences on the urban experience, with the existence of two distinct realities (tourist region X the periphery region). Based on theory of phenomenology, social representation, and using content analysis of film, it was noted that promotes to the visitor a trip segmented and disintegrated to daily life, culture and contact with the resident. Resident that, in largely part, lives in a unattended area, with no prospect of life (represented by Novo Horizonte Community). The confinement and segregation occurs even in his moments of leisure and cultural expressions (represented by Redinha‟s Beach), because the private an public leisure areas of tourism indirectly prevent access by people who can not contribute to the consumption on this places. This papper concluded that the tourism in Natal is an activity-phenomenon that directs and focuses on public investments for infrastructure tourist region (Ponta Negra Beach), in detriment of the poorest and periphery areas of the city

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The results of the research systematized on this analysis sought apprehend the linkage of the socio-educational service network, destined to adolescents who comply with socioeducational measure of confinement, in the region of the Seridó of the state of the Rio Grande do Norte, especially in the city of Caicó, central town of this region. The achievement of this study was stimulated by the interest in unraveling the contradictory reality imposed by neoliberal State, sparing the guarantee of rights, especially to these teens, who are seen as authors of violations and are stigmatized by capitalist society. The research was carried in the period July-September 2013, under critical perspective, using the documental analysis and the observational techniques and interviews with professionals of the Educational Center (CEDUC), of the Unified Health System (SUS), of the Social Policies of Social Assistance, and of the State Department of Education, which should make the service network that gravitates around the National System of Socio-educational Services (SINASE). The Statute of Children and Adolescents (ECA) and SINASE define that the application of socioeducational measures cannot occur isolated of the public policies, becoming indispensable the linkages of the system with the social policies of social assistance, education and health. However, it was observed that the neoliberal logic of the capitalist State has developed broken, disconnected, focal and superficial social policies, who fail give effect to the rights acquired beyond the legal sphere. In this perspective, it is possible affirm that the everyday of the Brazilian poor teens is marked by the action of the State, which aims to control those who disturb the order of capital, who threaten the production, the market, the consume and the private property. This way, actions are promoted criminalizing poverty and imprint a legal action over this expression of the social issue to the detriment of social policies that meet the real needs of adolescents. Face of this reality, it becomes necessary to put on the agenda of the here and now to fight for rights, aiming at a broad public debate involving professionals, researchers and social movements in support of the viability of rights, which aims to support reflections and to strengthen ways to confront this social problem. With the approximations of this study, it was learned that the struggle for rights is a fight for another project of society, beyond what is laid.

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Voice disorders (VD) in the elderly can interfere negatively in communication, emotional well-being and quality of life, conditions that correspond to greater exposure to illness and social isolation bringing consequent economic impact for the health system. It is assumed that institutionalized confinement, weakness and morbidity associated to nursing home (NH) contribute to transform VD an especially prevalent condition in institutionalized elderly, including those without cognitive impairment. Thus, the aim of this study was to determine the prevalence and associated factors of VD in NH elderly residents without cognitive impairment. There is no epidemiological diagnostic instruments of VD for elderly populations, so the first step of this study was dedicated to prepare and analyze the psychometric properties of a short, inexpensive and easy to use questionnaire named Screening for Voice Disorders in Older Adults (Rastreamento de Alterações Vocais em Idosos—RAVI). The methodological procedures of this step followed the guidelines of the Standards for Educational and Psychological Testing and contemplated validity evidence based on test content, based on response processes, based on internal structure and based on relations with other variables, as well as reliability analysis and clinical consistency. The result of the validation process showed that the RAVI final score generate valid and reliable interpretations for the epidemiological diagnosis of VD in the elderly, which endorsed the use of the questionnaire in the second stage of the study, performed in ten NH located in the city of Natal, Rio Grande do Norte. At this stage, data from socioeconomic and demographic variables, lifestyle, general health conditions and characterization of the institution were collected. It was performed a bivariate analysis and it was calculated the prevalence ratio as a magnitude association measure, with a confidence interval of 95%. The variables with p-value less than 0.20 were included in the multiple logistic regression model that followed the Forward selection method. The odds ratio found in the multivariate model was converted into prevalence ratio and the level of significance was 5%. The sample consisted of 117 subjects with predominance of females and average of 79.68 (± 7.92) years old. The prevalence of VD was 39.3% (95% CI: 30.4-48.1%). The multivariate model showed statistically significant association between VD and depressive symptoms, smoking for a year or more and selfreported hearing loss. In conclusion, VD is a prevalent health condition in NH elderly residents without cognitive impairment and is associated with factors involving psychosocial, lifestyle and communicative disability that require attention of managers and professionals involved with NH environment. Strategies to encourage communication and social integration, actions to combat smoking and minimizing the effects of hearing loss could stimulate the physical well-being, emotional and mental health of institutionalized elderly population, contributing to the vocal and communicative maintenance, a more effective social inclusion and better overall health condition.

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Leachates are effluent produced by decomposition of solid waste, they have complex composition and can be highly toxic. Therefore such percolated liquid should be collected and treated properly to avoid environmental contamination of soil and of water bodies. The objective of this study was to evaluate the toxicity through ecotoxicological tests with Ceriodaphnia dubia (Cladocera - Crustacea) of percolated liquids generated in two different systems of municipal solid waste (MSW) disposal in the city of Natal/ RN: A Sanitary Landfill in the Metropolitan Region of Natal/ RN, and in a dump off area. Furthermore, it was evaluated the possible contamination of the underground water of the dump off area. Two monthly samples were taken at four points between the months of May/2009 and January/2010. The Point "A" corresponds to the end of the pond leachate treatment in ASRMN; The Point "B" corresponds to a containment pond at the dump. The Point "C" is an area near one of the cells of the dump off area where the leachate outcrops; The Point "D" stands for an underground water well at the area. The last point, called "E" was sampled only once and corresponds to the slurry produced by temporary accumulation of solid waste in the open area of the dump. The ecotoxicological tests, acute and chronic, followed the ABNT 13373/2005 rules, with some modifications. The samples were characterized by measuring the pH number, the dissolved oxygen (DO), the salinity, BOD5, COD, Cd, Cu, Pb, Cr, Fe, Mg, Ni, and Zn. At Point A, the average number of EC50-48h ranged between 1.0% and 2.77% (v/v), showing a high toxicity of the leachate to C.dubia in all months. To this point, positive correlations were found between the EC50- 48 with precipitation. Negative correlations were found between the EC50- 48h with salinity. At point B there was no response of the acute exposure of organisms to the test samples. At point C the EC50-48h ranged from 17.68% to 35.36% in just two months of the five ones analyzed, not correlated meaning. Point D, the EC50-48h level ranged between 12.31% and 71.27%, showed a negative correlation with, only, precipitation. Although it was observed toxicity of underground water in the Landfill Area, there was no evidence of water contamination by leachate, however, due to the toxic character of this water, additional tests should be conducted to confirm the quality of water that is used for human supply. At point E there was no acute toxicity. These results support the dangers of inappropriate disposal of MSW to water bodies due to the high toxicity of the leachate produced highlighting the necessity of places of safe confinement and a treatment system more effective to it

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Due to the occurrence of diseases in the use of structural reinforcements in composites, with presentation of concrete blanket detachment, has been identified the need to evaluate the performance of concrete reinforced with glass fiber. This study aims to evaluate these concretes by means of testing methodologies, using concrete with low resistance with structural reinforcement for confinement by preimpregnated glass fiber and traditional fiberglass blanket. The first stage of work was the development of methodologies for analysis, opting for four types, such as the acoustic survey, strength to compressive, the pull-off and ultrasound. Next, tests were carried out using the four selected methodologies in 30 of proof-of-specimens by 5x10 cm, 15 were reinforced with the traditional fiberglass blanket with 5specimens exposed to test a marine environment of marine coastline of Natal-RN and 15 were reinforced with a pre-impregnated glass fiber blanket, as well as 5specimens exposed to a test environment of the marine coastline of Natal-RN. After conducting the acoustic survey, it has been verified a lack of delaminating and air bubbles in the samples, confirming the absence of gross shortcomings in the implementation of the ribs both the traditional fiberglass blanket and in the preimpregnated fiber glass blanket. After carrying out methods of pull-off and compressive strengthening test it was observed that the reinforced proof-bodies with pre-impregnated glass blanket showed maximum stresses higher than the traditional fiberglass blanket; consequently a greater grip with the formation of a smaller area of . fracture, unlike traditional glass mat, which showed lower maximum stresses, with a greater area of fracture. It was also found that the traditional fiberglass blanket presented detachment of blanket-concrete interface, unlike the pre-impregnated fiberglass blanket, which showed a better grip on the blanket-concrete interface. In the trial of ultrasound there was no presence of cracks in the blanket-concrete interface, yielding to both blankets good compactness of the concrete. At the end of this work, they were developed and proposed two methods of testing for evaluation of reinforced concrete structures with composites, for standardization, the acoustic survey and pull-off