5 resultados para 2,2,6,6, tetramethylpiperidine 1 oxyl 4 amino 4 carboxylic acid

em Universidade Federal do Rio Grande do Norte(UFRN)


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Ionic liquids (ILs) are organic compounds liquid at room temperature, good electrical conductors, with the potential to form as a means for electrolyte on electrolysis of water, in which the electrodes would not be subjected to such extreme conditions demanding chemistry [1]. This paper describes the synthesis, characterization and study of the feasibility of ionic liquid ionic liquid 1-methyl-3(2,6-(S)-dimethyloct-2-ene)-imidazole tetrafluoroborate (MDI-BF4) as electrolyte to produce hydrogen through electrolysis of water. The MDI-BF4 synthesized was characterized by thermal methods of analysis (Thermogravimetric Analysis - TG and Differential Scanning Calorimetry - DSC), mid-infrared spectroscopy with Fourier transform by method of attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance spectroscopy of hydrogen (NMR 1H) and cyclic voltammetry (CV). Where thermal methods were used to calculate the yield of the synthesis of MDI-BF4 which was 88.84%, characterized infrared spectroscopy functional groups of the compound and the binding B-F 1053 cm-1; the NMR 1H analyzed and compared with literature data defines the structure of MDI-BF4 and the current density achieved by MDI-BF4 in the voltammogram shows that the LI can conduct electrical current indicating that the MDI-BF4 is a good electrolyte, and that their behavior does not change with the increasing concentration of water

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Ionic liquids (ILs) are organic compounds liquid at room temperature, good electrical conductors, with the potential to form as a means for electrolyte on electrolysis of water, in which the electrodes would not be subjected to such extreme conditions demanding chemistry [1]. This paper describes the synthesis, characterization and study of the feasibility of ionic liquid ionic liquid 1-methyl-3(2,6-(S)-dimethyloct-2-ene)-imidazole tetrafluoroborate (MDI-BF4) as electrolyte to produce hydrogen through electrolysis of water. The MDI-BF4 synthesized was characterized by thermal methods of analysis (Thermogravimetric Analysis - TG and Differential Scanning Calorimetry - DSC), mid-infrared spectroscopy with Fourier transform by method of attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance spectroscopy of hydrogen (NMR 1H) and cyclic voltammetry (CV). Where thermal methods were used to calculate the yield of the synthesis of MDI-BF4 which was 88.84%, characterized infrared spectroscopy functional groups of the compound and the binding B-F 1053 cm-1; the NMR 1H analyzed and compared with literature data defines the structure of MDI-BF4 and the current density achieved by MDI-BF4 in the voltammogram shows that the LI can conduct electrical current indicating that the MDI-BF4 is a good electrolyte, and that their behavior does not change with the increasing concentration of water

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OBJETIVO: avaliar a sintomatologia climatérica e fatores relacionados entre mulheres dos meios urbano e rural do Rio Grande do Norte. MÉTODOS: estudo transversal, descritivo, envolvendo casuística de 261 mulheres climatéricas residentes em Natal e Mossoró (grupo urbano; n=130) e Uruaçu, em São Gonçalo do Amarante (grupo rural; n=131). A sintomatologia climatérica foi avaliada pelo Índice Menopausal de Blatt-Kupperman (IMBK) e Escala Climatérica de Greene (ECG). A análise estatística constou de comparações das medianas dos escores entre os grupos e regressão logística. Defi niram-se como “muito sintomáticas” as pacientes com escores ≥20, para ambos instrumentos (variável dependente). As variáveis independentes foram: idade, procedência, alfabetização, obesidade e prática de atividade física. RESULTADOS: o grupo urbano apresentou escores signifi cativamente superiores ao grupo rural, tanto para o IMBK (medianas de 26,0 e 17,0, respectivamente; p<0,0001), quanto para a ECG (medianas de 27,0 e 16,0, respectivamente; p<0,0001). Na amostra total, evidenciou-se que 56,3% (n=147) das mulheres foram classifi cadas como “muito sintomáticas”. Na comparação intergrupos, essa prevalência foi signifi cativamente mais elevada nas mulheres urbanas em relação às rurais (79,2 e 33,6%, respectivamente; p<0,05). Pela análise de regressão logística, evidenciou-se que a chance de pertencer ao grupo defi nido como “muito sintomáticas” foi maior para mulheres do meio urbano [odds ratio ajustado (OR)=7,1; 95% intervalo de confi ança a 95% (IC95%)=3,69-13,66] e alfabetizadas (OR=2,19; IC95%=1,16-4,13). A idade superior a 60 anos associou-se com menor chance de ocorrência de sintomas signifi cativos (OR=0,38; IC95%=0,17-0,87). CONCLUSÕES: a prevalência de sintomas climatéricos signifi cativos é menor em mulheres do meio rural, demonstrando que fatores socioculturais e ambientais estão fortemente relacionados ao surgimento dos sintomas climatéricos em nossa população.___________________________________ABSTRACT PURPOSE: to evaluate climacteric symptoms and related factors in women living in rural and urban areas of Rio Grande do Norte, Brazil. METHODS: a cross-sectional study involving 261 women in the climacteric was performed. A total of 130 women from Natal and Mossoró (urban group) and 131 from Uruaçu, in São Gonçalo do Amarante (rural group), were studied. Climacteric symptoms were assessed by the Blatt-Kupperman Menopausal Index (BKMI) and Greene Climacteric Scale (GCE). Statistical analysis involved comparison of median between groups and logistic regression analysis. Patients were defi ned as “very symptomatic” when the climacteric score was ≥20 for both questionnaires (dependent variable). Independent variables were: age, living area, schooling, obesity and physical activity. RESULTS: the urban group had signifi cantly higher scores than those of the rural group, both for BKMI (median of 26.0 and 17.0, respectively; p<0.0001) and for GCE (median of 27.0 and 16.0, respectively; p<0.0001). For the entire sample, a total of 56.3% (n=147) of the women were classifi ed as “very symptomatic”. This prevalence was signifi cantly higher in urban than in rural women (79.2 and 33.6%, respectively; p<0.05). Logistic regression analysis showed that the likelihood of belonging to the group defi ned as “very symptomatic” was greater for urban women [adjusted odds ratio (OR)=7.1; confi dence interval at 95% (95%CI)=3.69-13.66] who were literate (OR=2.19; 95%CI=1.16- 4.13). Individuals over the age of 60 years had less chance of having signifi cant symptoms (OR=0.38; 95%CI=0.17-0.87). CONCLUSIONS: the prevalence of signifi cant climacteric symptoms is less in women from a rural environment, showing that sociocultural and environmental factors are strongly related to the appearance of climacteric symptoms in our population

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Literature has demonstrated to the narrow relation between deleterious habits and the occurrence of malocclusion in minors of 5 years. The existence of these habits, however, already considered as risk factors, having also, its determinative ones, which present cultural dimensions and economic social, many of them related to the parents of the child, having in account that such habits if develop in phases in which the child establish a narrow relation of dependence. This study it had an objective to investigate the prevalence of deleterious buccal habits in children and its relation with the economic social and characteristics of the parents. It was developed an epidemiologist study of transversal character with interview, through daily pay-tested form, with 218 parents in the day of the National Campaign of Vaccination. In the cast of the variable that had composed the study, they had been used, as changeable dependents, the use of the baby's bottle, bottle and the digital suction, being considered as outcomes of the research. Amongst the independent variable, the economic social factors (type of occupation, number of children, civil state, sort, schooling and age) and staffs of the parents (self perception in oral health) had entered as the variable to be analyzed in the problems of the infantile odontology. The collected data had been submitted to the analysis descriptive and inferential statistics, being used the test qui-square and the analysis of the possibility reasons. As main results, it was found that breast feeding before the six months if presents as one of the main factors of risk for the use of baby's bottle (p< 0.001, OR= 2.8, I.C= 1.589 4.906), bottle (p< 0.001, OR= 3.7, I.C.= 2.076 6.624) and digital suction (p< 0.014, OR= 3.5, I.C.= 1.225 10.181). From the data found, one concludes that breast-feeding is considered a primordial factor for not the installation of deleterious oral habits and that the economic social and cultural factors can reflect in central way in the performance of this act

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Several studies are carried out with aim to establish parameters to determine biologic behavior of oral squamous cell carcinoma, in order this neoplasm presents high rates of morbidity and mortality. The purpose of present research was to performe a clinic, morphologic and immunohistochemical analysis by the expression of galectins 1, 3, 4 and 7 in 65 cases of tongue squamous cell carcinoma, correlating this expression with clinics (outcome of the disease, metastasis and clinical staging) and morphologic parameters (malignancy histologic gradation system). The clinical and morphologic parameters analysed and expression of galectins 1, 3, 4 and 7 were submitted to statistical analysis (Qui2 test), observing that can be utilized as indicators of the biological behavior of the tongue squamous cell carcinoma. The galectin 1 was expressed in 87,7% of cases studied and it exhibit statistically significant correlation with metastasis (p=0,033) and clinical staging (p=0,016), it is located mostly in the citoplasm of the stomal cells. The immunoexpression of galectin 3 in 87,7% of cases was correlated with the presence of metastasis (p=0,033) and malignancy histological gradation system (p=0,031), observed, mostly of cases, in tongue squamous cell carcinoma of malignancy high grading. The galectin 4 showed no statistical significance to any of the parameters evaluated. The expression of galectin 7 in 73,8% of cases showed statistically significant correlation with the malignancy histologic grading (p=0,005), which is marking exclusively found in neoplastic epithelial cells, in the mostly of cases, it is found in cytoplasm and membrane (50%). The expressive immunopositivy of the galectins 1, 3 and 7, observed in this research, leads us to suggest a broad participation of these proteins in oral carcinogenesis, and its possible use as markers of biological behavior and tumor progression in cases of squamous cell carcinoma of the tongue