Livia Ribeiro - Academia.edu (original) (raw)

Papers by Livia Ribeiro

Anais - CAT - Congresso de Administração e Tecnologia, Dec 1, 2016

Este estudo in vitro teve como objetivo, avaliar as deformacoes de implantes e componentes protet... more Este estudo in vitro teve como objetivo, avaliar as deformacoes de implantes e componentes proteticos de uma protese parcial fixa implantossuportada, submetida as cargas axiais por meio da extensometria eletrica. Foi confeccionado um modelo experimental, simulando um hemi-arco desdentado, referente aos elementos 15 ao 18, reabilitados com analogos de implantes osseointegrados, na posicao dos elementos 15 e 17, e um corpo de prova simulando uma protese parcial fixa metalica constituida de liga de Niquel-Cromo (Ni-Cr), com os ponticos localizados nos elementos 16 e 18, sendo este ultimo com extensao em cantilever. Na regiao cervical dos analogos e cervicais dos pilares, foram fixados quatro extensometros um em cada face, mesial, distal, vestibular e palatina. No corpo de prova foram fixados quatro extensometros na cervical da protese. O corpo de prova foi submetido a um teste de cargas axiais controladas, utilizando o sistema de aquisicao de dados AqDados e AqDAnalysis (ADS0500IP- Lynx). Os ensaios mecânicos, com cargas estaticas compressivas axiais de 150N, foram realizados em maquina universal de ensaio DL EMIC 2000 0,5mm/min. Os resultados obtidos neste estudo mostraram que todos os componentes avaliados apresentaram valores consistentes de deformacao por compressao e/ou tracao, em funcao do carregamento aplicado (p<0,0001). Desta forma, foi possivel concluir que as deformacoes observadas entre a regiao cervical do corpo de prova, pilares proteticos e analogos de implantes foram significativamente diferentes entre si (p<0,005 ou p<0,001), e que os fenomenos mecânicos observados foram de natureza deflectiva com caracteristicas de compressao e tracao. As comparacoes realizadas no plano horizontal mostraram diferencas estatisticamente significantes, na regiao dos analogos dos implantes, e as comparacoes realizadas no plano vertical exibiram diferencas significativas entre os componentes do sistema de um dos analogos estudados.

2019 54th International Universities Power Engineering Conference (UPEC), 2019

Lightning Discharges (LD) occurrence in distribution networks is a usual phenomenon, especially i... more Lightning Discharges (LD) occurrence in distribution networks is a usual phenomenon, especially in rural areas feeders. In order that the effects of this intense phenomenon do not cause extensive damage to distribution networks and consumers, simulations tools are necessary to enable the development and design of protection methods. In the present work, models for direct LD simulation of each distribution network element are presented in a concentrated form, as well as their typical values. The ATP-EMTP simulation software was chosen. Thus, this article can be taken as a basis for further studies development on LD. Simulation results present an analysis of the LD incidence at different locations along the feeder.

A escassez da agua tem sido um dos temas mais discutidos por ONG's e pela ONU nos ultimos ano... more A escassez da agua tem sido um dos temas mais discutidos por ONG's e pela ONU nos ultimos anos. A medida que aumenta a populacao e sua demanda por bens manufaturados e produtos agricolas, cresce tambem a demanda por agua, que e um recurso natural, limitado e imprescindivel para a vida. Buscando incentivar a preservacao desse recurso tao precioso, foram criadas normas para auxiliar no processo de aproveitamento da agua da chuva. Este trabalho visa apresentar como deve ser feito o processo de captacao, economia gerada, e tambem um exemplo pratico e de uso caseiro onde a agua da chuva e aproveitada para diversos fins.

A inflacao e tida como o aumento simultâneo nos precos, nao apenas de um, mais de varios bens ou ... more A inflacao e tida como o aumento simultâneo nos precos, nao apenas de um, mais de varios bens ou servicos, numa dada regiao, em certo periodo de tempo e que resulta na perda do poder aquisitivo da moeda. A presente pesquisa faz uma analise dos impactos inflacionarios observaveis na renda, preco dos produtos e desemprego, no ramo de supermercados da cidade de Manhuacu-MG. O metodo de pesquisa utilizado foi o questionario, pois abrange um maior numero de pessoas com maior facilidade; ainda foi utilizada a pesquisa exploratoria, pois se trata de uma pesquisa pioneira da variavel inflacao, na cidade e no ramo de pesquisa e ainda, foi utilizada a tecnica de levantamento para a obtencao de dados relevante a pesquisa. Os resultados apontam que a renda e os produtos sofreram alteracoes, porem, em relacao ao desemprego pode-se notar que nao houve alteracoes por causa dos indices inflacionarios.

International Journal of Advanced Engineering Research and Science, 2020

Journal of Porous Materials, 2018

The search for appropriate supports for enzyme immobilization has attracted increasing interest i... more The search for appropriate supports for enzyme immobilization has attracted increasing interest in the field of biocatalysis. Immobilized enzymes are catalysts of enormous industrial interest because they combine the advantages of heterogeneous catalysis with the high selectivity and mild operational conditions of enzymes. This study evaluated the use of different organic molecules as functionalizing agents anchored on the silanol groups present on the surface of mesoporous materials such as SBA-15. This modification aims to increase the interaction of the enzyme invertase to the support, allowing for a greater amount of this biocatalyst to be immobilized. The hexagonal mesoporous material SBA-15, which has pores in the range of 40–60 Å, was synthesized and modified by the following organic compounds: trimethoxyphenylsilane, vinyltrimethoxysilane and 3-aminopropyltriethoxysilane (APTES). APTES showed the best results in increasing the anchoring of enzymes on the material’s surface, providing a specific amount of enzyme loaded onto the surface of approximately 80% and, thus, showing successful functionalization.

Revista Ciência Agrícola, 2018

A crescente necessidade de encontrar alternativas para fazer frente às resistências de certos mic... more A crescente necessidade de encontrar alternativas para fazer frente às resistências de certos micro-organismos a compostos já existentes no mercado tem atraído a pesquisa de bioprospecção de fungos endofíticos como fontes de bioativos. Esses compostos podem se apresentar como tóxicos e/ou mortais para outros micro-organismos, além de possuírem atividades hormonais, antibióticas, antifúngicas e antiparasitárias. Objetivou-se verificar a produção de bioativos por fungos endofiticos associados a plantas do Semiárido alagoano. Foram isolados fungos de Barauna (Schinopsis brasiliensis), Quixabeira (Bumelia sertorum Mart.), Juazeiro (Ziziphus joazeiro Mart.), Bonome (Maytenus rigida Mart), Aroeira-Vermelha (Schinus terebinthifolius), Pau-Ferro (Caesalpinia ferrea), Pereiro (Aspidosperma pyrifolium), Angico-vermelho (Anadenanthera colubrina), Imburana (Commiphora leptophloeos), e Umbuzeiro (Spondias tuberosa). Os isolamentos, foram realizados pelo método das diluições seriadas e semeadura ...

Environmental science and pollution research international, Jan 15, 2018

The impact of alcohol consumption on periodontal disease and tooth loss is still under debate. Th... more The impact of alcohol consumption on periodontal disease and tooth loss is still under debate. The aim of this cross-sectional study was to evaluate the association between alcohol dependence and both periodontal diseases and tooth loss in Brazilian native Indians. Full mouth periodontal examination was performed and tooth loss was clinically evaluated in a representative sample of 225 Indians (≥ 19 years). Sociodemographic, oral health-related data, and alcohol dependence were evaluated using structured questionnaires. The subjects were categorized as either alcohol-dependent or non-dependent according to the Alcohol Use Disorders Identification Test results. Severe periodontal disease was defined in individuals with ≥ 2 proximal sites with a clinical attachment level ≥ 6 mm, not on the same tooth, and ≥ 1 proximal site with a probing depth ≥ 5 mm. Tooth loss was categorized as one or more missing teeth, or no missing teeth. Bivariate models followed by logistic regression were use...

Materialwissenschaft und Werkstofftechnik, 2017

Marine pollution bulletin, Jan 30, 2017

The characterization of inorganic elements in the produced water (PW) samples is a difficult task... more The characterization of inorganic elements in the produced water (PW) samples is a difficult task because of the complexity of the matrix. This work deals with a study of a methodology for dissolved Fe quantification in PW from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE). The procedure is based on the CPE using PAN as complexing agent and Triton X-114 as surfactant. The best conditions for Fe extraction parameters were studied using a Box-Behnken design. The proposed method presented a LOQ of 0.010μgmL(-1) and LOD of 0.003μgmL(-1). The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of 2.54%. The accuracy of the method was assessed by recovery experiments of Fe spiked that presented recovery of 103.28%. The method was applied with satisfactory performance to determine Fe by FAAS in PW samples.

Zeitschrift Fur Naturforschung C a Journal of Biosciences, 2013

Journal of the American Society of Hypertension : JASH, May 2, 2016

The aim of this cross-sectional study was to evaluate the association between dental infections a... more The aim of this cross-sectional study was to evaluate the association between dental infections and systemic diseases in the Indigenous population of Brazil. A representative sample of 225 Indigenous (≥19 years) was assessed. The T-test and bivariate and logistic models were used to assess the associations of diabetes, hypertension, and obesity with dental caries and destructive periodontal disease. After adjustments for covariates, dental caries were associated with hypertension (odds ratio = 1.95; 95% confidence interval: 1.03-3.66; P = .04). Individuals with destructive periodontal disease had a higher systolic blood pressure (124 ± 20.34 mm Hg) than those without destructive periodontal disease (117.52 ± 16.54 mm Hg; P = .01). In conclusion, dental infections were found to be associated with hypertension in the present population. Thus, patients diagnosed with hypertension should be referred for dental evaluation and vice versa.

Fuente: Informe de Gestión 2012 (Adaptado por los Autores) 2.6.4.2. Proceso de producción Fuente:... more Fuente: Informe de Gestión 2012 (Adaptado por los Autores) 2.6.4.2. Proceso de producción Fuente: Información Pollo Andino (Realizado por los autores) Diagrama 3: Diagrama Proceso Productivo Pollo Andino S.A

International dental journal, Jan 19, 2015

The aim of this cross-sectional study was to evaluate the risk indicators of tooth loss in adult ... more The aim of this cross-sectional study was to evaluate the risk indicators of tooth loss in adult Kiriri Indians from Brazil. A representative sample of 225 Indians (≥19 years of age) was assessed. Interviews using a structured written questionnaire were performed to collect data on demographics and socio-economic status, and health-related data. Probing depth, the distance between the cement-enamel junction and the free gingival margin, and decayed, missing or filled teeth were evaluated. Bivariate and logistic models were used to assess associations between tooth loss and age, sex, income, education, diabetic status, smoking habits, dental caries, severe periodontitis, plaque index and previous dental visit. Eighty per cent of subjects had lost one tooth or more, and 20% had lost eight teeth or more. Mean (±standard deviation) tooth loss was 5.09 (±5.83) teeth. After adjustment for covariates, loss of one tooth or more was associated with older age [≥35 years; odds ratio (OR) = 4.0...

Talanta, 2016

Paints, a complex matrix, have a variable composition that is dependent on the application. In th... more Paints, a complex matrix, have a variable composition that is dependent on the application. In this work, a new wet digestion procedure for the determination of Al, As, Ba, Cd, Cr, Cu, Mn, Ni, Pb, Sn, Sr, Ti and Zn in paint samples using inductively coupled plasma optical emission spectrometry (ICP OES) has been developed. An experimental design approach was employed to determine the optimal conditions for achieving complete solubilization and/or decomposition in the sample preparation method. An efficient sample preparation was developed that consisted of a pre-digestion step at 40°C for 20min using 1mL of HNO3 to eliminate organic solvents followed by digestion at 120°C for 3h using 5mL of HCl and 1mL of HF in a block digestion. The proposed procedure promotes the complete solubilization of different bases of paints at low temperature and atmospheric pressure. The accuracy was determined by addition/recovery tests and comparing the results with those obtained using the ASTM D335-85a standard sample preparation method. The limits of quantification were 1.78, 0.11, 0.006, 0.006, 0.01, 0.04, 0.006, 0.006, 0.02, 0.07, 0.30, 1.30 and 0.30mgkg(-1) for Al, As, Ba, Cd, Cr, Cu,Mn, Ni, Pb, Sn, Sr, Ti and Zn, respectively. The proposed method was applied for the analysis of inorganics via the ICP OES of paints with different colors and bases used to cover wall surfaces.

Revista de Administração da Unimep, 2009

Page 1. Revista de Administração da UNIMEP Maio / Agosto 2009, v.7, n.2. Página 118 A Importâ... more Page 1. Revista de Administração da UNIMEP Maio / Agosto 2009, v.7, n.2. Página 118 A Importância da Logística na Gestão de Resíduos Sólidos em um Pequeno Município Mineiro: Decisões Estratégicas no Processo de Transporte e Roteirização ...

Journal of Sustainable Bioenergy Systems, 2014

Biodiesel production by enzymatic catalysis has been the subject of much research for developing ... more Biodiesel production by enzymatic catalysis has been the subject of much research for developing processes that can potentially compete with other types of catalysis. The objective of this study was to investigate the variables that influenced the transesterification of coconut oil catalyzed by immobilized lipase for biodiesel production. A full 2 4 factorial design with the variables temperature (40˚C-60˚C), enzyme concentration (3%-7%), oil-ethanol ratio (1:6-1:10) and alcohol type (methanol-ethanol) was performed. The best conversion result (80.5%) was obtained using ethanol with a higher temperature, molar ratio and enzyme concentration. The obtained yields showed that the results attained with ethanol were more significant when compared with methanol.