6 resultados para Perigos teratogênicos

em Universidade Federal do Rio Grande do Norte(UFRN)


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The intake of adequate quantities of food, including those rich in vitamins, is necessary for a healthy life. The lack of vitamin A has been characterized as a public health problem in developing countries, however, a high intake of vitamin A can result in toxic and teratogenics effects. High concentrations of vitamin A have been observed in the livers of animals. The objective of this study was to assess the levels of retinol in chicken livers and verify the effect of frozen storage on these levels. 64 livers from two chicken strains, Cobb and Ross, were used, came from four different farms. We examined 32 livers from each strain, 8 samples from each farm. Liver sample were homogenized individually, then 4 aliquots were taken from each sample. One of aliquots was analyzed immediately after slaughter (T0), the others were analyzed after 30, 60 and 90 days of storage at -18oC (T30, T60 and T90, respectively). Retinol dosage in the liver was determined by High Performance Liquid Chromatography (HPLC). The levels of retinol varied significantly according to the strain. The mean retinol value in the fresh samples was 6678.0 ± 1337.7 and 8324.1 ± 1158.5 µg/100g in the Cobb and Ross strain, respectively. Values of 4258 ± 918.7 ± 1391.7 and 4650.5 ± 1391.7 μg/100g were found after 90 days of storage for Cobb and Ross strain, respectively. The liver freezing caused a significant reduction in their levels of retinol, causing a loss of up to 44% with respect to fresh livers. The reduction in retinol levels occurred from 30 days of storage. Even with the losses from the frozen, the ingestion of a typical portion of 100 g of liver, regardless the chicken strain analyzed, surpass all recommendations of consumption and the maximum tolerable intake of vitamin A (3000 μg/day) for adults

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L accès et la permanence des étudiants à l université sont très présents dans les débats actuels relatifs à l'enseignement supérieur. De nombreuses mesures sont prises dans les politiques d'accès dans le but de réduire les inégalités et d'encourager les étudiants ayant moins de chances d'entrer dans l'enseignement supérieur, comme les étudiants issus de l'enseignement public, qui ont encore un niveau inférieur à celui souhaité. Lorsque ces élèves réussissent à terminer leurs études secondaires, passer l'examen d'entrée et réussir leur entrée dans l'enseignement supérieur ils se considèrent comme « victorieux ». Cette étude (pour le Master de l UFRN), développée au sein du groupe de recherche de la formation et professionnalisation des enseignants (PPGed / UFRN), vise à étudier la trajectoire des élèves issus des écoles publiques qui accèdent à une université publique. Nous avons interviewé 12 étudiants, six de l'Université fédérale de Rio Grande do Norte (UFRN) et 6 de l'Université d'État de Bahia (UNEB) inscrits à différents cours du premier cycle (Licence). Nous cherchons savoir comment s est déroulé leurs parcours au sein de l'Université, notamment en ce qui concerne la préparation aux examens d'entrée à l université (Vestibular) , la motivation du choix de cours, la première année à l'université, les habitudes d'étude, la relation avec l'apprentissage et les perspectives quant à l'avenir des élèves interrogés. Nous nous sommes référés aux travaux menés par Zago (2006), Ramalho (2003), Charlot (1997), Galland et Gruel (2009), Coulon (2008), Tinto (1993), Doray et l'équipe canadienne du CIRST (2009). L'entrée à l'université comporte un triple processus, institutionnel (formelles et informelles), intellectuel (composantes cognitives et académiques) et social (vie sociale au sein de l'université). L'étudiant entre à l'université et y trouve une nouvelle culture, de nouvelles connaissances et devra apprendre à être universitaire. Apprendre à surmonter le moment de l étrangeté et bien passer par le processus de l'apprentissage des règles, des codes de son nouveau statut et s accommoder de sa position d étudiant à l'université, arrive enfin, le temps d'affiliation, c'est à dire, le moment de l'admission où l'étudiant se sent comme un «vétéran», et qu il peut dire que les dangers de l'abandon sont passés et qu il pourra continuer son parcours avec succès. Cette étude vise à apporter des connaissances nouvelles sur les étudiants issus des écoles publiques, comme contribution au domaine des politiques d'accès et de permanence à l université et de soutien pédagogique au sein de cette institution

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This essay: The perception environmental of the Passo da Pátria dwellers in Natal-RN has as its goal, investigate the perception of the dwellers in an degraded environment in ways of urbanizing, at the Potengi River riverine. This is an area in zone environmental risk, which year after year was even forgotten by the municipality, but which attracted a huge estranger public because of its facility in access urbanized areas in Natal at the same rate of its natural riches from the mangue and the sea. Front to problems of economical nature as scarce job offers, its habitants build their dwellings without any kind order or social protection, occupying an inadequate space for the well keeping of the urban environmental equilibrium. The analyzed community is exposed to water floods, tropical diseases, and to criminal problems like gangsters and drug dealers. We propose in such essay observe the connivance of the dwellers with the natural environment and their expectations o citizen transformations. This essay has as its bases the studies of Tuan (1983), Nunes (2000) and principally in Wilhem Reich (1998) in who we found our concept of perception, that here plays like an important analytical category to confront our corpus. Our first chapter debates the concept of place, not in an historical materialistic vision, but within an phenomenological survey; the second chapter presents the impacts of the urbanization in the community perception, and in the third one is analyzed the perception of the Passo da Pátria community. Based in this analyzes we confirmed that the conditions of living of the dwellers are extremely dangerous; but, the most of them do not see such dangers, even saying that are well living in its community

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The textile industry is one of the most polluting in the world (AHMEDCHEKKAT et al. 2011), generating wastewater with high organic loading. Among the pollutants present in these effluents are dyes, substances with complex structures, toxic and carcinogenic characteristics, besides having a strong staining. Improper disposal of these substances to the environment, without performing a pre-treatment can cause major environmental impacts. The objective this thesis to use a technique of electrochemical oxidation of boron doped diamond anode, BDD, for the treatment of a synthetic dye and a textile real effluent. In addition to studying the behavior of different electrolytes (HClO4, H3PO4, NaCl and Na2SO4) and current densities (15, 60, 90 and 120 mA.cm-2 ), and compare the methods with Rhodamine B (RhB) photolysis, electrolysis and photoelectrocatalytic using H3PO4 and Na2SO4. Electrochemical oxidation studies were performed in different ratio sp3 /sp2 of BDD with solution of RhB. To achieve these objectives, analysis of pH, conductivity, UV-visible, TOC, HPLC and GC-MS were developed. Based on the results with the Rhodamine B, it was observed that in all cases occurred at mineralization, independent of electrolyte and current density, but these parameters affect the speed and efficiency of mineralization. The radiation of light was favorable during the electrolysis of RhB with phosphate and sulfate. Regarding the oxidation in BDD anode with different ratio sp3 /sp2 (165, 176, 206, 220, 262 e 329), with lower carbon-sp3 had a longer favoring the electrochemical conversion of RhB, instead of combustion. The greater the carbon content on the anodes BDD took the biggest favor of direct electrochemical oxidation

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This work has as object the elaboration of social environmental indicator of disaster risk that are present in precarious areas of human occupation, related to intense environmental dynamic from the perspective of the studies about the subject in Geography. The District of Mãe Luiza in Natal, capital city of Rio Grande do Norte, was defined as the study area. The place was chosen because it presents –historically- several vulnerability conditions and exposure to disaster risk. After a local social environmental description, two indexes were elaborated: the Social Vulnerability Index (SVI or IVS in Portuguese), based on 17 (seventeen) variables arranged on a questionnaire addressed to the population nucleus of the district, on regular grid (systematic sampling), classified into 5 (five) levels of SV from the weighted average; and the Physical and Natural Exposure to the Mass Movements Index (EMMI or IEMM in Portuguese) which had 16 (sixteen) variables that feature conditions of exposure to the mass movements in the district with classified levels from the weighted average of 1 (one) to 5 (five). The relationship between these two results, specialized in the district map, produced the Social Environmental Vulnerability Index (SEVI or IVSA in Portuguese) of Mãe Luiza, also classified into 5 (five) levels, following the Boolean logic correlation for cartographic overlay with use of computer software ArcGIS v.9.3, being named as: Very Low; low; average; high; and Very High Environmental Vulnerability in District. The study is based on the methodology proposed by Guerra et al (2009) for EMMI and by Almeida (2010) for SVI. They were modified and adapted according to the local reality, producing a new methodology in this study area. It was concluded that the neighborhood has most of its area with High and Very High Socio-environmental vulnerability to disasters, defined seven (7) critical areas, with Very High IVSA, and hazards associated with mass movements or flooding. In the end, the main issues that were found, such as generating elements for proposing mitigation measures and/or the proposed interventions were enumerated, related to structural order of vulnerability factors: how low constructive pattern of households; poor urban drainage; Real Estate forsaken in landslide routes; infrastructure ready access roads and slope containment. And social: as a lack of education about environmental risk; income and education of residents; presence of persons with limited mobility and/or those with special needs. This reality highlights the need for urgent action applied to the resolution and/or reduction of these problems, which is focusing the end of this work.

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The intake of adequate quantities of food, including those rich in vitamins, is necessary for a healthy life. The lack of vitamin A has been characterized as a public health problem in developing countries, however, a high intake of vitamin A can result in toxic and teratogenics effects. High concentrations of vitamin A have been observed in the livers of animals. The objective of this study was to assess the levels of retinol in chicken livers and verify the effect of frozen storage on these levels. 64 livers from two chicken strains, Cobb and Ross, were used, came from four different farms. We examined 32 livers from each strain, 8 samples from each farm. Liver sample were homogenized individually, then 4 aliquots were taken from each sample. One of aliquots was analyzed immediately after slaughter (T0), the others were analyzed after 30, 60 and 90 days of storage at -18oC (T30, T60 and T90, respectively). Retinol dosage in the liver was determined by High Performance Liquid Chromatography (HPLC). The levels of retinol varied significantly according to the strain. The mean retinol value in the fresh samples was 6678.0 ± 1337.7 and 8324.1 ± 1158.5 µg/100g in the Cobb and Ross strain, respectively. Values of 4258 ± 918.7 ± 1391.7 and 4650.5 ± 1391.7 μg/100g were found after 90 days of storage for Cobb and Ross strain, respectively. The liver freezing caused a significant reduction in their levels of retinol, causing a loss of up to 44% with respect to fresh livers. The reduction in retinol levels occurred from 30 days of storage. Even with the losses from the frozen, the ingestion of a typical portion of 100 g of liver, regardless the chicken strain analyzed, surpass all recommendations of consumption and the maximum tolerable intake of vitamin A (3000 μg/day) for adults