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In this original work, the specie Maclura tinctoria (L.) D. Don Ex Steud, as known as amoreira , was evaluated under many aspects. The macromolecular constituent s composition, the phenolic compounds level, antioxidant and antimicrobial activity of the bark and wood were studied. The corresponding percents of total extractives level, acid insoluble lignin (Klason´s lignin), acid soluble lignin, holocelluloses, hemicelluloses and α-celluloses were an average of the values for the wood: 10.79 ± 1.98; 21.47 ± 1.25; 1.28 ± 0,00; 69.43 ± 2.16; 23.59 ± 0.36; 46.02 ± 1.53 (%), and for the bark 50.64 ± 2.47; 18.77 ± 1.20; 0.45 ± 0.01; 29.14 ± 1.90; 8.78 ± 0.42 and 21.4 ± 0,77 (%). The level of total phenols obtained with methanol/water 4:1 (v/v) and acetone/water 7:3 (v/v) extracts using Folin-Ciocalteau method for the wood was 38.43 ± 0.42 and 45.34 ± 0.86 and 35.03 ± 0.94 e 43.17 ± 1.18 for the bark, expressed in Gallic acid equivalents (GAC) per gram of sample. The proanthocyanidins level obtained was 5.11± 0.59 for wood and 6.51 ± 0.62 for bark, in catechin equivalents per gram of sample. The antioxidant activity was determined by DPPH (2,2-diphenyl-1-picrylhydrazyl) for the wood and bark extracts, with IC50=18.74 and IC50 = 20.97 μg mL-1 , for wood and bark, respectively. The crude extracts from wood and bark from Maclura tinctoria (L.) has presented growth inhibition of the tested periodontopathogenic bacteria. The MIC of the crude extracts were in the range of 200 and 400 μg mL-1 for wood extracts and from 20 to 400 μg mL-1 for bark extracts, against the control microorganisms tested. Neste estudo inédito, a espécie Maclura tinctoria (L.) D. Don Ex Steud., comumente conhecida como amoreira, foi avaliada a composição dos constituintes macromoleculares, teor de compostos fenólicos, atividade antioxidante e antimicrobiana da madeira e casca desta espécie. Os teores de extrativos totais, lignina insolúvel em ácido (lignina de Klason), lignina solúvel em ácido, holocelulose, hemiceluloses e α-celulose, corresponderam às médias, para a madeira de 10,79 ± 1,98; 21,47 ± 1,25; 1,28 ± 0,00; 69,43 ± 2,16; 23,59 ± 0,36; 46,02 ± 1,53 (%), e para a casca de 50,64 ± 2,47; 18,77 ± 1,20; 0,45 ± 0,01; 29,14 ± 1,90; 8,78 ± 0,42 e 21,4 ± 0,77 (%). A partir de extratos metanol/água 4:1(v/v) e acetona/água 7:3(v/v), obteve-se o teor de fenóis totais de acordo com o método de Folin-Ciocalteau foi de 38,43 ± 0,42 e 45,34 ± 0,86 para a madeira e de 35,03 ± 0,94 e 43,17 ± 1,18 para a casca, expressos em equivalente de ácido gálico/grama de amostra, já o teor de proantocianidinas foi de 5,11± 0,59 e 6,51 ± 0,62 para a madeira e de 3,88 ± 0,12 e 4,85 ± 0,06 para a casca em equivalentes de catequina/grama de amostra. A atividade antioxidante foi avaliada pelo método de sequestro do radical livre DPPH˙ (2,2-difenil-1-picrilidrazil), obtendo-se para o extrato metanólico da madeira (CE50 = 18,74 μg mL-1) e da casca (CE50 = 20,97 μg mL-1). Os extratos brutos da madeira e da casca de amoreira foram capazes de inibir o crescimento das bactérias periodontopatogênicas testadas, apresentando efeito antimicrobiano. As concentrações inibitórias mínimas dos extratos brutos variaram entre 200 e 400 μg mL-1 para os extratos da madeira e 20 a 400 μg mL-1 para os extratos da cascas frente aos microrganismos indicadores utilizados nos ensaios. Mestre em Química

Made available in DSpace on 2016-04-28T20:19:23Z (GMT). No. of bitstreams: 1 2009 - Antonio Carlos Vilela.pdf: 1562012 bytes, checksum: 6336ba47d980fb5d06f60391e0fc9e7f (MD5) Previous issue date: 2009-06-09 This study has had as objective, the identification of the main factors responsible for the loss of competitiveness in the Brazilian?s printing and coated industry. Coated wood free. For this identification was applied a strategy of data evaluation through structured interviews with four professionals with experience in the Paper Sector. It was used information issued in articles, magazines, dissertations, newspapers and on top of that primary and secondary data from the Pulp and Paper Sector were used, specifically the coated wood free for printing segment. The study had as assumption that there was loss of competitiveness in the Brazilian market, and the main factor responsible for this loss could be attributed to a systemic factor, the exchange rate. There was an increase of importation and reduction of exportation in the period of the study. The main factors identified in the interviews in sequence of importance and according to the interviewers were; exchange rate, the illegal usage of duty free operation during the importation and the lack of update the industrial equipments in the Brazilian Mills The currency, as a main factor of competitiveness loss for the Coated paper sector and it was confirmed through the evaluation of secondary figures of importation grow and exportation reduction in the period of 2003 till 2008. Other factor, the illegal usage of duty free operation during the importation, was based only in the perception of the interviewers; there were no dada available due to the subjectivity of this topic. The third factor, the lack of update the industrial equipments in the Brazilian Mills appointed during the interviews. It could be confirmed in the analyze of the world?s fastest paper machines and more competitive in the world in comparison with Brazilian?s paper machines which speed are very far from the more competitive machines in the world. The Brazil is not even mentioned in this article of machines caparison. When the factors that determine the competitiveness of printing coated papers are analyzed in group, the conclusion is that Brazil is not competitive in this segment due to several business factors. The currency that is a systemic factor and appears in the periods of currency valuation works in the process of exposure of the low competitiveness already existent. Este trabalho teve como objetivo identificar os principais fatores que levaram a ind?stria brasileira de papel de imprimir revestido, o Couch?, ? perda de competitividade. Para identifica??o desses fatores foi aplicada a estrat?gia de an?lise de dados atrav?s da realiza??o de entrevista estruturada com quatro profissionais experientes ligados ao setor de pap?is, informa??es publicadas em artigos, revistas, teses e disserta??es, alem dos dados prim?rios e secund?rios do setor de celulose e papel, especificamente os do segmento do papel de imprimir revestidos ? o Couch?. Dentro deste objetivo foi adotada a suposi??o de que houve perda de competitividade no mercado brasileiro, e que um dos principais fatores da perda desta competitividade poderia ser atribu?do a um fator sist?mico, o cambio, havendo aumento das importa??es e redu??o das exporta??es no per?odo estudado. Os principais fatores identificados nas entrevistas, por ordem de import?ncia e segundo os entrevistados, foram: o cambio, a pr?tica desleal de isen??o tribut?ria e a falta de atualiza??o do parque industrial brasileiro. O cambio, como principal fator de perda de competitividade do setor de pap?is revestidos, pode ser corroborado atrav?s da an?lise dos dados secund?rios de importa??o crescente e exporta??o declinante no per?odo analisado de 2003 a 2008. O outro fator de pr?tica desleal da isen??o tribut?ria ficou apenas na percep??o dos entrevistados, n?o havendo dados dispon?veis para sua avalia??o pelo pr?prio grau de subjetividade deste tema. O terceiro fator de perda de competitividade apontado nas entrevistas foi a falta de atualiza??o do parque industrial brasileiro. Isto pode ser confirmado pela an?lise dos dados das m?quinas de papel mais velozes e competitivas do mundo em compara??o com as do Brasil, cujas velocidades est?o muito aqu?m das mais competitivas do mundo. O Brasil n?o ? sequer citado no artigo comparativo. Quando os fatores determinantes da competitividade dos pap?is de imprimir revestidos s?o analisados em conjunto, observa-se que o Brasil n?o ? competitivo neste segmento devido a diversos fatores empresarias. Quando a quest?o cambial, que ? um fator sist?mico, aparece em per?odos de valoriza??o cambial, este somente exp?e e agrava mais ainda esta baixa competitividade existente.

Made available in DSpace on 2016-04-28T20:19:27Z (GMT). No. of bitstreams: 1 2009 - Simone Daniel Pereira.pdf: 539585 bytes, checksum: ecafc7836af384f97d846d0fe4d46e7c (MD5) Previous issue date: 2009-06-07 In the late two decades, the telecommunications sector passed through great transformations. On the one hand, the advent of the microelectronics base has provoked a technological revolution in the telecommunications industry, which resulted in new services, new transmission and switching equipment and the convergence with others segments of the electronic complex. On the other hand, a set of institutional and regulatory changes introduced in some developed countries, has brought important modifications in the organization of the sector all over the world. At the same time, with the increasing internationalization and integration processes between national economies (the well known globalization process), the telecommunications sector became the essential infrastructure for the participation of citizens, firms, regions and countries in the new international environment. The telecommunications industry is changing due to regulatory reasons and for emerging technologies that transformed the industry framework. Regulatory changes facilitate the privatization wave that happened in the end of the 1990 s, fostering competition in the sector. The technology convergence of telephony, information technology, television and internet, creates a new paradigm for this market. The market reconfiguration leads to acquisitions and mergers, motivated by the economy of scale necessary to bare the high fixed costs of technological infrastructure. O setor de telecomunica??es vem passando por enormes transforma??es nas duas ?ltimas d?cadas. De um lado, a introdu??o da microeletr?nica provocou uma revolu??o tecnol?gica na ind?stria de telecomunica??es, que resultou no surgimento de novos servi?os, novos equipamentos de transmiss?o e comuta??o, bem como na converg?ncia com outros setores do complexo eletr?nico. De outro lado, um conjunto de mudan?as institucionais e regulat?rias foram rapidamente absolvidas nos pa?ses mais desenvolvidos, provocando altera??es significativas na estrutura do setor em todo o mundo. Paralelamente, o avan?o da internacionaliza??o e da integra??o entre as economias nacionais, amplamente conhecido como globaliza??o, tornou as telecomunica??es a infra-estrutura t?cnica fundamental para a inser??o de cidad?os, firmas, regi?es e pa?ses no ambiente econ?mico e social internacional. A ind?stria de telecomunica??es vem sofrendo mudan?as motivadas por quest?es regulat?rias e por tecnologias emergentes que transformam o cen?rio da ind?stria. As mudan?as regulat?rias propiciaram todo o movimento de privatiza??es que aconteceram no final dos anos 90, promovendo a competi??o no setor. A converg?ncia de tecnologias de telefonia, tecnologia de informa??o, televis?o e internet, criam um novo paradigma para o mercado. O realinhamento do mercado resulta em movimentos de fus?es e aquisi??es, motivados pelos ganhos de escala necess?rios para fazer frente aos altos custos fixos de infra-estrutura.