Refino de silício por tratamento a vácuo

Este trabalho visa investigar a remoção a vácuo de fósforo do silício grau metalúrgico (SiGM) (98,5% a 99% de Si).\ud Foram realizados experimentos de fusão em forno de indução a vácuo, variando parâmetros como temperatura, tempo\ud e relação área exposta ao vácuo / volume de silício. Os resultados de análise química foram obtidos por plasma acoplado\ud indutivamente (ICP) e avaliados com base em aspectos termodinâmicos e cinéticos da reação de vaporização do fósforo\ud no silício. Obteve-se refino de 33 para cerca de 1,5 ppm de P em três horas, concluindo-se que a etapa de evaporação é\ud a etapa controladora do processo para os parâmetros de temperatura, pressão e agitação utilizados, e que o refino por\ud este processo é tecnicamente viável.Companhia Ferroligas Minas GeraisBNDE

Modelagem logística aplicada ao extrativismo do pequi

Pequi plays an important economic and social role in extractivism in northern Minas Gerais, being exploited in an environmentally sustainable way. Its socioeconomic value can be observed from the collection to consumption, being considered, therefore, the gold of the cerrado, a source of income for countless families. However, one of the problems in the fruit extraction chain is the lack of logistics for the flow of production, which generates a high cost and compromises the profitability of extractivists. Thus, this work proposes a transport logistics for the exploration of pequi in the North of Minas from the creation of a model in the city of Japonvar/MG. For the work, a literature review, on-site visits, systematic observation and treatment of information collected on ArcGIS and TransCAD platforms were carried out. The modeling was developed using the Geographic Information System-GIS, which allowed for the mapping of the municipality's producing areas, the creation of facilities for the flow of the fruit and the routing of vehicles with a focus on minimizing transport costs. As a result, facilities were obtained, the qualification of access roads to the production areas and the routing of vehicles for collection.O pequi exerce um importante papel econômico e social no extrativismo norte mineiro, sendo explorado de forma ambientalmente sustentável. O seu valor socioeconômico pode ser observado da coleta ao consumo, sendo considerado, por isso, o ouro do cerrado, fonte de renda para inúmeras famílias. No entanto, identifica-se como um dos problemas da cadeia de extração do fruto a falta de logística para o escoamento da produção, o que gera um elevado custo e compromete a lucratividade dos extrativistas. Assim, o presente trabalho propõe uma logística de transporte para a exploração do pequi no Norte de Minas a partir da criação de uma modelagem no município de Japonvar/MG. Para o trabalho, foi feita uma revisão bibliográfica, visitas in loco, observação sistemática e tratamento das informações coletadas nas plataformas ArcGIS e TransCAD. A modelagem foi desenvolvida utilizando o Sistema de Informação Geográfico-SIG, que permitiu o mapeamento das áreas produtoras do município, a criação de facilidades para escoamento do fruto e o roteamento dos veículos com foco na minimização dos custos com o transporte. Como resultado, obtiveram-se as facilidades, a qualificação das vias de acesso às áreas produtoras e a roteirização dos veículos para a coleta

Monitoring of erosivity in the area of contribution of the reservoir of the hidroeletric Cachoeira Dourada, GO/MG

The erosivity index (EI30) was determined as well as their spacing in the contribution basins of the Cachoeira Dourada hydroelectric plant reservoir at the border with states Goiás and Minas Gerais, located between coordinates 48º 32’ to 49º 34’ W and 18º 20’ to 18º 53’ N. Data from 8 locations referring to 30-year average monthly and annual precipitations were used. An annual average precipitation of 1,441mm was found during that period, being the highest index in January and the lowest in July, with 7.5mm. The EI30 varied from 7,100 MJ to 8,500 MJ mm (ha h)-1, whose most significant period was concentrated between the months of october to march, with 7,880.3 MJ mm (ha h)-1, corresponding to 94% of the annual average EI30 index. The average variation coefficient of precipitations for all seasons was 82.73%. There is an irregular distribution of rain in the region and, thus, an uneven spacing of the erosivity indexes within the reservoir influence area. The highest precipitations coincide with the period of soil preparation and development of annual cycle plants, mainly soybean and corn

The expansion of stricto sensu graduate studies in education in Brazil

It examines the quantitative expansion of stricto sensu graduate studies in the area of education in Brazil, based on the student dimension of its programs, considering their regional differences, type of course, and legal status. The quantitative approach and the documentary research method composed the methodological design of the investigation. The sample consisted of the total number of students in the course, admitted students, and graduated students in Graduate Programs in Education (GPEs), from 2004 to 2020. The data sets referring to the students were collected in the open data repository of the Coordination for the Improvement of Higher Education Personnel (CAPES, in Portuguese). Data analysis used descriptive statistics techniques, through the R language. There was an increase in the number of students in the courses, admitted students, and graduated students in GPEs in Brazil during the investigated period. The asymmetries, although still existing, were mitigated. The North and Northeast regions are still underrepresented. The participation of the private sector is still timid, if compared to the hegemony of the public sector, even when it comes to professional master’s degrees. In 2020 there was a decrease in all indicators, characterizing an inflection in the expansion process. These results are likely to contribute to support decision-making by managers and public policy makers.Examina a expansão quantitativa da pós-graduação stricto sensu na área de educação no Brasil, com esteio na dimensão discente de seus programas, ponderando suas diferenças regionais, de tipo de curso e de estatuto jurídico. A abordagem quantitativa e o método da pesquisa documental compuseram o desenho metodológico da investigação. A amostra se constituiu do total de estudantes do curso, de admitidos e de titulados em Programas de Pós-Graduação em Educação (PPGEs), de 2004 a 2020. Os datasets referentes aos estudantes foram coletados no repositório de dados abertos da Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). A análise dos dados empregou técnicas da estatística descritiva, por meio da linguagem R. Houve aumento no número de discentes, admitidos e titulados em PPGEs no Brasil, durante o período investigado. As assimetrias, apesar de ainda existentes, foram mitigadas. Norte e Nordeste ainda são regiões que se encontram sub-representadas. A participação do setor privado ainda é tímida, se comparada à hegemonia do setor público, mesmo nos mestrados profissionais. No ano de 2020, registrou-se diminuição em todos os indicadores, caracterizando uma inflexão no processo de expansão. Esses resultados são passíveis de contribuir para subsidiar a tomada de decisão dos gestores e formuladores de políticas públicas

An analysis of Brazilian sugarcane bagasse ash behavior under thermal gasification.

Background: Ashes from sugarcane were analyzed by X-ray fluorescence, ash content, X-ray diffraction, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). FactSage 6.4 database software was used to estimate viscosity at high temperatures (900 - 1550°C) of them. Results: The results showed that although ashes from sugarcane bagasse contain silica, most of its SiO2 is from soil contamination. Higher and lower silica samples treated at 1350°C for 20 minutes showed that the fine portion of fraction of the ashes melted at this temperature. Conclusions: The melting phase could act as sticking flux for the coarse silica particles on the gasifier bottom wall, which could compromise the gasification process

INFLAMAÇÃO: PRINCIPAIS MEDIADORES QUÍMICOS

Inflamação é um processo biológico complexo que envolve componentes vasculares, celulares e uma diversidade de substâncias solúveis, apresentando como sinais clínicos característicos rubor, calor, edema, dor e alterações funcionais. A finalidade do processo inflamatório é remover o estímulo lesivo e iniciar o processo de recuperação tecidual local. Este processo ocorre através dos mediadores químicos da inflamação derivados de células sendo pré-formados em grânulos no interior das mesmas, podendo também serem sintetizados no sítio da inflamação quando há presença de estímulo nocivo. Objetiva-se neste trabalho realizar uma atualização bibliográfica a partir de artigos científicos, sobre o estudo da ação dos principais mediadores químicos presentes na inflamação. A pesquisa bibliográfica foi desenvolvida através de uma revisão acerca da produção cientifica existente sobre a temática abordada. Para isto, foram analisados artigos publicados entre os períodos de 2010 à 2018, utilizando as bases de dados eletrônicas: Google Acadêmico, SciELO (Scientific Eletronic Library Online), PubMed (US National Library of Medicine), e LILACS (Literatura Latino-Americana e do Caribe em Ciências da Saúde), nos idiomas português, inglês e espanhol. Os descritores utilizados foram: “Inflamação”, “Mediadores Inflamatórios” e “Mediadores Químico da inflamação”. Os critérios de inclusão adotados para os artigos em análise foram: a) artigos que abordem aspectos gerais referentes a mediadores químicos da inflamação; b) artigos completos e gratuitos. Dentre os principais mediadores químicos da inflamação estão as aminas vasoativas compostas histamina e serotonina, os metabólitos do ácido araquidônico compostos por prostaglandinas, leucotrienos e lipoxinas e as citocinas que são constituídas por fator de necrose tumoral, interleucina-1, quimiocinas, espécies reativas do oxigênio, o óxido nítrico, entre outros fatores. Conclui-se então que o processo inflamatório desenvolvem-se a partir de reações complexas em tecidos que consistem principalmente na resposta dos vasos sanguíneos e leucócitos. As principais defesas do organismo contra corpos estranhos são proteínas plasmáticas e leucócitos circulantes, assim como os fagócitos teciduais derivados destas. As reações vasculares e celulares da inflamação são disparadas por fatores solúveis produzidos por varias células ou derivados de proteínas do plasma e geradas ou ativadas em resposta aos estímulos inflamatórios. Tais mediadores iniciam e amplificam a resposta inflamatória determinando seu padrão, severidade e manifestações clinicas e patológicas

Conventional versus flap-protected free gingival graft: a multicenter randomized clinical trial

The purpose of this study was to compare the outcomes of a modified gingival graft technique, in which the released flap is positioned and sutured over the graft, with the conventional free gingival graft (FGG) procedure, when both are used for gingival augmentation. A 12-month, multicenter parallel randomized controlled trial was conducted. Subjects with buccal RT2 gingival recessions and keratinized tissue width (KTW) < 2 mm in at least one mandibular incisor were randomized to control group (n = 20; conventional FGG) or test group (n = 20; modified FGG; flap sutured over FGG using sling sutures). The primary outcome (KTW) was measured at baseline and after 3, 6 and 12 months, as was keratinized tissue thickness (KTT). Postoperative pain (POP) and analgesic intake were also recorded. Both techniques promoted a significant increase in KTW and KTT when compared to baseline (p < 0.05) with no significant differences between groups (KTW change of 6.1±1.5 mm and 5.4±1.6 mm, for control and test, respectively; p=0.16). However, test group patients reported less POP after 7 days and used less analgesic medication than control group patients (p < 0.05). We concluded that the modified FGG was comparable to conventional FGG in augmenting keratinized tissue width and thickness at mandibular incisors, but resulted in less patient morbidity

Isolation and functional characterization of a cotton ubiquitination-related promoter and 5'UTR that drives high levels of expression in root and flower tissues

<p>Abstract</p> <p>Background</p> <p>Cotton (<it>Gossypium </it>spp.) is an important crop worldwide that provides raw material to 40% of the textile fiber industry. Important traits have been studied aiming the development of genetically modified crops including resistance to insect and diseases, and tolerance to drought, cold and herbicide. Therefore, the characterization of promoters and regulatory regions is also important to achieve high gene expression and/or a specific expression pattern. Commonly, genes involved in ubiquitination pathways are highly and differentially expressed. In this study, we analyzed the expression of a cotton ubiquitin-conjugating enzyme (E2) family member with no previous characterization.</p> <p>Results</p> <p>Nucleotide analysis revealed high identity with cotton <it>E2 </it>homologues. Multiple alignment showed a premature stop codon, which prevents the encoding of the conserved cysteine residue at the <it>E2 </it>active site, and an intron that is spliced in <it>E2 </it>homologues, but not in <it>GhGDRP85</it>. The <it>GhGDRP85 </it>gene is highly expressed in different organs of cotton plants, and has high transcript levels in roots. Its promoter (uceApro2) and the 5'UTR compose a regulatory region named uceA1.7, and were isolated from cotton and studied in <it>Arabidopsis thaliana</it>. uceA1.7 shows strong expression levels, equaling or surpassing the expression levels of CaMV35S. The uceA1.7 regulatory sequence drives GUS expression 7-fold higher in flowers, 2-fold in roots and at similar levels in leaves and stems. GUS expression levels are decreased 7- to 15-fold when its 5'UTR is absent in uceApro2.</p> <p>Conclusions</p> <p>uceA1.7 is a strong constitutive regulatory sequence composed of a promoter (uceApro2) and its 5'UTR that will be useful in genetic transformation of dicots, having high potential to drive high levels of transgene expression in crops, particularly for traits desirable in flower and root tissues.</p

Prevalence of oral mucosal lesions in a brazilian military police population

Background: Data obtained from oral health surveys are very important for identifying disease-susceptible groups and for developing dental care and prevention programs. So, the purpose of the current article was to investigate the prevalence of oral mucosa lesions (OMLs) in a population of Brazilian police. Material and Methods: Interviews and oral cavity examinations were performed on a sample of 395 police officers who were randomly selected by the calibrated researcher. The number of individuals was obtained by a sample calculation using the finite population correction. The diagnostic criteria were based on the WHO (1997) criteria and adapted to Brazilian surveys. Results: In total, 8.61% of the population presented some OML. Traumatic injuries and benign migratory glossitis (BMG) were the most prevalent lesions. Conclusions: The prevalence of potentially malignant disorders was lower than among the Brazilian population. The most prevalent lesion among the police officers was related to trauma. Patients dissatisfied with oral health had a higher risk of presenting OMLs