169 research outputs found
Environmental education in secondary schools in the region of Ribeirão Preto (SP, Brazil): how teachers' views of the environment determine their teaching and some reflections on chemistry teachers' higher education
During short courses, 95 secondary school teachers from 49 state schools and 421 students from the Ribeirão Preto region (in Sao Paulo state, Brazil, with a population of 530,000) were asked to fill in different questionnaires. The points raised in the teacher's questionnaire were used as a guide to establish a continuous dialogue during the short courses. Most of the schools claimed to have some kind of environmental education (EE). Based on the questionnaires and dialogues we analyzed how the teachers' perceptions on EE reflect on the views secondary students hold about their own responsibility for preserving the environment. The role of universities in the preparation of chemistry teachers capable of effectively approaching EE is also discussed
Modified electrodes prepared with polyphenolic film containing ruthenium complex and metal ligand anchored by azo covalent bond
This work presents two new modified carbon electrodes which were prepared via the polymerization of a phenolic moiety previously functionalized with azo groups (bipyridine and 2-methoxypyridine) as key structures to anchor the desired ligands. The syntheses of BAP (4-([2,2’]-bipyridinyl-4-ylazo)-phenol) and PAPmethoxy (5-(4-hidroxyphenylazo) pyridin-2-methoxy) were simple to perform, gave good yields and the monomers were easily electropolymerized resulting in chemically and mechanically stable modified electrodes. The PAP-methoxy ME formed stable complexes with Cd, Cu and Pb in aqueous media at open circuit and produced well defined redox peaks, showing good potential for future analytical applications. The BAP monomer was used to produce a ruthenium complex (BAP-Ru) which was electropolymerized from +0.50 to +0.75V (vs. Ag/AgCl) to leave the ruthenium available to act as a catalyst. The BAP-Ru ME was able to oxidize a variety of organic substrates with good selectivity. The yields obtained were either similar to, or better than, those obtained by homogeneous catalysis using a similar ruthenium catalyst or when this type of catalyst is supported in a carbon paste electrode.Este trabalho apresenta dois novos eletrodos de grafite modificados que foram preparados via polimerização da função fenólica, previamente funcionalizada por grupos azo (bipiridina e 2-metoxipiridina), que atuam como estruturas chaves para a ancoragem de ligantes de interesse. As sínteses dos monômeros BAP (4-([2,2’]bipiridinil-4-ilazo)-fenol) e PAPmetóxi (5-(4-hidroxifenilazo)piridin-2-metóxi) foram simples, deram bons rendimentos e os monômeros foram facilmente eletropolimerizados, levando à formação de eletrodos modificados (EM) química e mecanicamente estáveis. Em solução aquosa e em circuito aberto, o EM PAP-metóxi formou complexos estáveis com Cd, Cu e Pb, produzindo picos redox bem definidos, demonstrando o grande potencial deste eletrodo para futuras aplicações analíticas. O monômero BAP foi utilizado para produzir um complexo de rutênio (BAP-Ru) que foi eletropolimerizado entre +0.50 e +0.75V (vs. Ag/AgCl), permitindo que o rutênio permanecesse disponível para atuar como catalisador. O EM BAP-Ru oxidou seletivamente uma variedade de substratos orgânicos dando produtos com rendimentos próximos ou melhores que aqueles obtidos por catálise homogênea com complexos de rutênio similares, ou quando este tipo de catalisador é impregnado em pasta de carbono.CNPqCoordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES
An overview of how the curricula taken by future chemistry teachers in southeastern Brazil's public universities approach environmental issues
This work analysed the contents of 701 disciplines from 22 chemistry courses that prepare chemistry teachers in 16 public Universities in Southeastern Brazil. Only a small number (23) of disciplines showed an explicit relationship between human activities and the environment. A total of 11 theoretical and 193 experimental disciplines explored to some extent scientific and technological aspects related to the environment, but did not include their relationship with society. As the experimental disciplines supposedly include some kind of waste treatment, this may explain why secondary school chemistry teachers work mainly on recycling programs and waste issues at their schools. The aim of this work is to provide information on which to base a much needed discussion about how to better prepare our chemistry teachers to act as Environmental Educators at school, as the Brazilian Education Legislation requires
Métodos de baixo custo para purificação de reagentes e controle da contaminação para a determinação de metais traços em águas naturais
Educação, currículo escolar e protagonismo juvenil: os desafios da educação na contemporaneidade
Resumo: Este artigo se insere no debate sobre educação e política, abordando a relação entre educação, currículo escolar e violência simbólica na perspectiva de adolescentes entre 12 e 17 anos que cumprem medidas socioeducativas no CREAS (Centro de Referência Especializada da Assistência Social) de Vitória, Brasil. Através de nossas análises, percebemos que a educação apresenta desafios, contradições e tensões decorrentes principalmente da organização da sociedade contemporânea, que acaba por reforçar a exclusão desses alunos. Além disso, apontamos a discrepância entre a regulamentação dessas medidas e o cotidiano escolar bem como a falta de protagonismo dos sujeitos envolvidos no cumprimento dessas medidas como alguns obstáculos do processo de inclusão desses adolescentes.
Palavras-chave: Educação; Currículo Escolar; Protagonismo Juvenil e Violência.
Resumen: Este artículo se inserta en el debate sobre educación y política, con un enfoque en la relación entre educación, plan de estudios y violencia simbólica en la perspectiva del adolescente entre 12 y 17 años que cumple una “medida socioeducativa” en el CREAS (Centro de Referência Especializado de la Asistencia Social) de Vitória, Brasil. Mediante nuestros análisis percibimos que la educación presenta desafíos, contradicciones y tensiones derivadas principalmente de la organización de la sociedad contemporánea, que refuerza la exclusión. Además, señalamos la discrepancia entre la regulación de la medida, y el cotidiano escolar, así como la falta de protagonismo de los sujetos involucrados en el cumplimiento de las medidas como algunos obstáculos del proceso de inclusión de estos adolescentes.
Palabras clave: Educación; Plan de Estudios; Protagonismo Juvenil y Violencia.
Abstract: The theme of this article is inserted in the debate on education and politics in a way that relates education, curriculum and symbolic violence in the perspective of adolescents at the age range of 12 to 17 years who are under socio-educational measures in the CREAS (Specialized Center of Reference in Social Work) of Vitoria, Brazil. Throughout some analysis we realized that education presents challenges, contradictions and tensions mainly due to the organization of contemporary society, which reinforces exclusion. In addition, we identified the discrepancy between the regulation of these measures and the school routine, and the lack of leadership of the individuals complying with the measures as some of the obstacles these adolescents face in the social inclusion process.
Keywords: Education; School Curriculum; Youth Participation and Violence
O sapo dourado do arquivo pessoal de Mário de Andrade analisado com o método não destrutivo de fluorescênciade raios X
Purification and characterization of a collagenase from Penicillium sp. UCP 1286 by polyethylene glycol-phosphate aqueous two-phase system
Collagenases are proteolytic enzymes capable of degrading both native and denatured collagen, reported to be applied in industrial, medical and biotechnological sectors. Liquid-liquid extraction using aqueous two-phase system (ATPS) is one of the most promising bioseparation techniques, which can substitute difficult solid-liquid separation processes, offering many advantages over conventional methods including low-processing time, low-cost material and low-energy consumption. The collagenase produced by Penicillium sp. UCP 1286 showed a stronger affinity for the bottom salt-rich phase, where the highest levels of collagenolytic activity were observed at the center point runs, using 15.0% (w/w) PEG 3350 g/mol and 12.5% (w/w) phosphate salt at pH 7.0 and concentration. The enzyme was characterized by thermal stability, pH tolerance and effect of inhibitors, showing optimal collagenolytic activity at 37 °C and pH 9.0 and proved to be a serine protease. ATPS showed high efficiency in the collagenase purification, confirmed by a single band in SDS/PAGE, and can in fact be applied as a quick and inexpensive alternative method.This work was supported by the National Council of Technological and Scientific Development (CNPq) and Coordination for the Improvement of Higher Education Personnel (CAPES). Sara Silvério also acknowledges her post-doc grant (SFRH/BPD/88584/2012) from FCT (SFRH/BPD/88584/2012) (Portuguese Science and Technology Foundation), Portugal
Seroconversion in asymptomatic COVID-19 pediatric patients with rheumatic diseases of one tertiary referral hospital
Objectives: To evaluate seroconverted asymptomatic COVID-19 in pediatric Autoimmune Rheumatic Diseases (ARDs) patients and to identify the risk factors related to contagion.
Methods: A cross-sectional study was conducted in March 2021, before vaccination of children and adolescents in Brazil, including 77 pediatric ARDs patients, followed at a tertiary hospital and 45 healthy controls, all of them without a previous diagnosis of COVID-19. Data was obtained by a questionnaire with demographic data, symptoms compatible with COVID-19 over the previous year, and contact with people with confirmed COVID-19. Patient's medical records were reviewed to access data regarding disease and current medications. A qualitative immunochromatographic SARS-CoV-2 test was performed on all participants.
Results: Patients and controls were similar in terms of female gender (70.1% vs. 57.8%, p = 0.173), age (14 vs. 13 years, p = 0.269) and SARS-CoV-2 positive serology (22% vs. 15.5%, p = 0.481). 80.5% of rheumatic patients were in use of immunosuppressive drugs: 27.3% of them used corticosteroids (33.3% in high doses), and 7.8% on immunobiologicals. No statistical differences were found between positive (n = 17) and negative serology (n = 60) patients regarding demographic/socioeconomic data, contact with people with confirmed COVID-19, use and number of immunosuppressive drugs, use and dose of corticosteroids, use of hydroxychloroquine and immunobiological drugs (p > 0.05).
Conclusions: Pediatric rheumatic disease patients were infected at the same rate as healthy ones. Neither the underlying pathology nor its immunosuppressive treatment seemed to interfere with contagion risk
Trypanosoma cruzi Adjuvants Potentiate T Cell-Mediated Immunity Induced by a NY-ESO-1 Based Antitumor Vaccine
Immunological adjuvants that induce T cell-mediate immunity (TCMI) with the least side effects are needed for the development of human vaccines. Glycoinositolphospholipids (GIPL) and CpGs oligodeoxynucleotides (CpG ODNs) derived from the protozoa parasite Trypanosoma cruzi induce potent pro-inflammatory reaction through activation of Toll-Like Receptor (TLR)4 and TLR9, respectively. Here, using mouse models, we tested the T. cruzi derived TLR agonists as immunological adjuvants in an antitumor vaccine. For comparison, we used well-established TLR agonists, such as the bacterial derived monophosphoryl lipid A (MPL), lipopeptide (Pam3Cys), and CpG ODN. All tested TLR agonists were comparable to induce antibody responses, whereas significant differences were noticed in their ability to elicit CD4+ T and CD8+ T cell responses. In particular, both GIPLs (GTH, and GY) and CpG ODNs (B344, B297 and B128) derived from T. cruzi elicited interferon-gamma (IFN-γ) production by CD4+ T cells. On the other hand, the parasite derived CpG ODNs, but not GIPLs, elicited a potent IFN-γ response by CD8+ T lymphocytes. The side effects were also evaluated by local pain (hypernociception). The intensity of hypernociception induced by vaccination was alleviated by administration of an analgesic drug without affecting protective immunity. Finally, the level of protective immunity against the NY-ESO-1 expressing melanoma was associated with the magnitude of both CD4+ T and CD8+ T cell responses elicited by a specific immunological adjuvant
Therapeutic dose of Ginkgo biloba extract 761 may alter the urine excretion of Wistar rats
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